I chose Storyteller, Method Actor, and Butt-kicker.
As someone said above, it's the stories that get me excited. A casual dungeon crawl is ok, but it's nothing compared to an overarching campaign with Evil Artifacts (tm), Twisted Villians (tm), and Epic PCs (r). I create PCs with intricate backgrounds, histories, connections, and plot hooks.
When I say Method Actor, I mean I like to get into my character. But I try not to act like an idiot or keep anyone else from enjoying the game (the importance of the Story comes first in my mind). I have done stupid things in game, but that had more to do with my mistakes than "well, he would've done that."
And finally Butt-kicker because an exciting combat is just so dern fun.
Edit: I also love hanging out with my friends, but I didn't choose casual gamer, because I'm really not casual. I can hang out with my friends any time (and I often do). Getting together to game is a rare occurence, so when we do that I want to really play.