Gaining Experience in the World of Warcraft.
As soon as you enter the world, you'll go through a short introduction to your race and how they enter the world, as well as a nice view of your starting area. Immediately you will be faced with a NPC (non-player character, basically a computer generized character that hands out quests/rewards) that has a yellow question mark over his head. that's a quest, right-click to interact and get it. In your quest Log (default key "L") it will appear, read the instructions, and do as it says (I can't stretch the importance of READING a quest, they will almost always tell you where to go to and what to do) . When you have completed the quest and are near the person you hand it in to, a yellow dot will appear on your mini-map (top righthand side of your screen) Also, the NPC will have a yellow question mark over his head. (almost all NPC's are stationary, so you won't have to worry about chasing them down to hand in a quest) When you turn in the quest, you will see that you have gained a large amount of experience in your general chat log (bottom left)

Combat
here is where i can only give you a few pointers. How you fight is completely up to you, find a groove of fighting (class, race and server can all make a big difference to your enjoyment) that you find fun, if you find yourself dieing alot or having troubles taking out one monster, then try some different spell combinations, or even make a new character. I suggest a paladin for a newbie, they are really hard to kill, not saying you have to stick with it, its just a good character to take some hits while you get your legs. Other than that, heres the basics. Your spellbook (default key "P") contains your spells (explained below) Drag the spells you use most often from your spellbook onto your "toolbar" (bottom left of your screen, its just a bunch of empty buttons.) set your most often used spell to whatever is easiest to hit, because you'll be hitting it ALOT. also, if you hit esc and go to "interface options" ---> "Advanced Options" you can enable additional taskbars which you can then link keys to by hitting escape and going to "Key Bindings" also note that your main toolbar is set to the default keys 1 through 0 in their respective order.

But basically, your spells are what seperate you from the "Mobs" (NPC's whose sole purpose is for you to kill to complete quests and gain experience, and score some phat lewt) While the mobs might have one or two spells they cast once or twice, you'll be unleashing a whirlwind of button clicks that do anything from damage, heal or even turn things into sheep. (seriously, mages polymorph), if you find yourself with little or no health at the end of a fight, odds are your not chaining enough spells together or your getting them in to slowly (practise getting one spell in as soon as another ends) and while melee fighters are lacking in the "frostbolt-firebolt-heal magic" they have numerous combat abilitys that work the same way as spells.

By now you'll have gotten some experience (this is measured on the purple bar on the bottom of your screen, also, note that if you have spent time inside of an Inn or capital city, a small marker will appear ahead of your experience bar, and the bar itself will be blue, this means that you have "rested experience" which means that when you kill something, you will get the experience as well as an additional 1/2 of the experience from the kill untill the bar hits the marker. quests cause the marker to move ahead and dont reward extra experience).

When that purple/blue bar reaches the end, you gain a level. if you dont have the expansion, you can only get to 60 (dont even THINk about that, its a long way off), but if you have the expac, you can hit the almighty 70. Every two levels starting from level 2 (2,4,6,8 and so on) you will be able to train new skills or better versions of old spells from your classes respective trainer. (found in most capital cities as well as your starting towns.)

At level 10 you get to choose your talents (default "N"). BE CAREFUL!!!!!! These desicions will last you all the way to level 70 unless you want to pay a hefty sum. And I know your not a pro, but stick to one "tree"( each class has three "trees" to put talents points in, if you played diablo 2 you'll know what i mean, if not, a tree is basically a line of specialization, for instance, mages have Arcane, Frost, and Fire, each tree's talents improve their respective spells. I.e a talents in the frost tree reduces the cast time of your frost bolt. Makes sense Huh? Once you get some more experience in the game and think you've got a character you want to stick with for a bit, choose your talents wisely, i suggest taking 10 minutes to read each talent, find out which tree best helps the spells you use most often, and only put talents into things you KNOW will help you. if your at a higher level (40-50) and you stuck to one tree, you get a pretty decent spell gained through a talent (mages last frost talent is a water elemental they can summon) You can split your points through all three trees if you think that will help your character best, it's not my place to say. Also, never, EVER ask, whats the best "spec"(a spec is the way someone has distributed their talents points", i.e if a mage says "im specced 20/10/20" that means he has 20 talent points in arcane, 10 in fire, and 20 in frost") Someones spec isn't always going to work out for you, they could be using completely different spells than you, it might take one or to trys, but eventually you'll get a spec thats perfect for you.
The Community and Etiquitte
There are many of those in world of warcraft who belive that it's ok to run up and take a chest you just cleared all the mobs away from, but let's face it, they ruin the game for a cheap laugh for themselves.

Basic courtesy dictates that you ask someone if they would like to join your group to help kill something. But instead what you get is people whispering you saying "Heal mara for us" (mara is an instance, one of those neat things you get to discover on your own). Also, never, EVER run up and take something without asking someone. (mining allows you to get metal ores from little deposits that appear once in a while out in the world, and lots of people will run up and mine it while you kill something beside it (you cant mine and fight at the same time) then say "oh sorry i thought you we're just killing this mob in the middle of no where for no reason at all" and run off with your ore.

Basically, Don't do anything to anyone else you wouldn't like dont to yourself, it's a cliche, but believe me, bad reputations build fast, and they can completely ruin a character unles you want to pay for it to be transferred to another server.

Proffesions
Time to choose your job. Proffesions in WoW are tradeskills, allowing you to fabricate items ranging from cloth armor to plate armor to guns to mechanical chickens to potions to... well.. just about anything you could possibly need. heres the basic rundown

Gathering Proffesions
Herbalism - allows you to track plants on your minimap and harvest them
Skinning - allows you to use a skinning knife to collect leather from fallen beasts
Mining - allows you to use a mining pick to dig up ores found in deposits, deposits appear on the minimap

Manufacturing Proffesions
Alchemy - Allows you to turn herbs found from herbalism into potions that provide temporary bonuses to stats or regenerate health and mana. (useful for any class really, never a bad choice)

Blacksmithing - Allows you to turn metal from mining into armor, weapons and a few other things

Engineering - Allows you to turn metal from mining into gadgets, bombs and guns, as well as dozens of other neat little things

Leatherworking - allows you to turn leather from skinning into armor and a few other things

Jewelcrafting - allows you to turn gems and metals found from mining into rings, amulets, trinkets and various other items

Tailoring - Allows you to turn cloth found in the world into cloth armor and a few other things

You can train two of any of the above skills, And there are two ways to do so

For money: go with two gathering proffesions, you can sell the materials on the auction house to people who need them for their own proffesions for quite a bit of gold

For yourself: go with a gathering and a manufacturing that go with eachother and will work for you (don't choose tailoring if your a warrior, the cloth armor isn't going to help. and stick to something like skinning/leatherworking so you can gather your own materials)

Most proffesions will require some kind of item that must be in your inventory to be able to perform the proffesion (you have to have a blacksmiths hammer in your backpack as well as be present at a forge/anvil in order to actually make something using blacksmithing.

PVP!
Ok, so you've got your foothold, you've got a character that has some greens, a decent spec (you think) and a good weapon. Head to the nearest capital city and ask a guard for the Battlemaster. Run your but up to the little flag on your map and que in for whatever is your level and you feel like doing. Heres the basic rundown of the battlegrounds

Warsong Gulch
10 Vs 10
goal: capture the flag 3 times to win
size: roughly the size of your level 1-6 zones.
Level req: level 10 or over.

(also keep in mind that you wont be facing level 60's at level 10 in a bg (battleground), there are brackets for 10-19, 20-29,30-39 and so on up to level 70. Although if you are in the lower half of your bracket you will be getting killed alot)

Arathi Basin
15 Vs 15
Goal: There are 5 areas that your team can hold. You must click on the flag at each area to capture it, once captured, that area will start awarding you points. For each point you have captured, the faster your points go up. Right click an enemys flag to capture it.
Size: A little under twice as big as warsong Gulch.
Level Req: 20 or over

Alterac Valley
40 vs 40 *matches can be anywhere from 20 vs 20 to 40 vs 40, depending on the amount of people that want to join.
goal: Kill the enemy NPC, deep within the enemys base. This also combines a slight arathi basin strategy, with areas you can capture that spawn npc guards to defend your base, the more areas you capture, the less guards, the easier it is to get to the Final boss.
Size: a but smaller than durotar (orc start zone)
level req: 50 or over

For every battleground you win, you are awarded three marks of honor for that battleground which will appear in your inventory and for every loss, you get one. (wsg gives you warsong gulch marks of honor, ab is arathi basin marks of honor etc). You can combine these with the honor you get from killing an enemy player (must be a real person, not mpc) to buy things near the battlegrounds portal entrances, or in your citys PvP rewards building. These rewards range from level 18-70 and are good quality. (weapons, armor, potions and other goodies) You are also rewarded honor points for killing enemy players out in the wilderness too, so dont be afraid to attack that alliance as he's bandaging up.