I am familiar with this 'World of Warcraft" you speak of...
As a matter of fact- it has ruined my social life lol. I am an avid WoW player. I am in a guild composed of people I work with, I have several high level characters and again, I have no social life because I would rather sit at home.
Be prepared my friend. WoW is definatley fun. Almost unanimously one of the best games ever created... I mean EVER. It has millions of players in countries all over the world. BUT- if you really want to get anywhere you will need to invest time and, unfortunately, more money in it. It is a level based MMORPG, which basically means you will "level" you character by killing things and completing quests... Both of which are in great supply. An almost never ending supply to be exact.
The level cap is 70 and it is estimated to take about 17 months to 2 years to reach that point- by a person who plays every single day. I have been stuck on WoW for far too long, but again, IMO it is the best game I have ever played. Years later and it still has replay value as if I just got it off the shelf every time I log on. I feel it is well worth the 15 bucks a month, and obviously so many millions of others do as well.
Have fun with it, but try not to start skipping work to hit level 45, thats a good way to loose a job. Or a girlfriend....or a social life...