I Am Quickly Getting Addicted to WoW!!

My brother recently introduced me to playing mmorpg games. I have never played a single game like this in my life and I am finding it hard to get interested. I really want something to help me pass the time and I think this would do the trick, but I have absolutely no idea what I am doing. I have tried reading the books that came along with the game he got me and I have used the in game tutorials, but I am still lost.

The game he gave me was World of Warcraft. He has played it for quite a few years and really seems to enjoy it, but obviously he knows what he is doing. I guess I am looking for some tips on how to play the game. I need to know how a person just experiencing the game for the first time would go about getting started. I have gotten as far as creating a character and killing stuff, but I am fairly certain there is more to it than that. I know the basics like picking up quests and what kind of gear to pick up for myself but that is about as much as I know. I have no idea where anything is, what I am supposed to be looking for and how to use my keys to play instead of using my mouse so much. A lot of people have told me to try and find a UI that suits me but I do not even know what that is. How am I supposed to find one that suits me if I do not even know what I am looking for? I am beginning to think that maybe the game is too advanced for me or my brain simply does not want to interpret how to play. Help!