Burnout is awesome. I have 3, Takedown (4), and Revenge (5). They consistently add good new features to each game, it's one of the best franchises I've ever played.
Fable is a game everyone raves about. I played it for an hour, thoroughly enjoyed it, and then it stopped working, and they won't let me take it back.
Knights of the Old Republic is fun too, it's a good mix of live and turn-based role playing.
Definitely get Super Monkey Ball DX, one of the absolute best games on Gamecube, brought to other platforms.
I really liked Prince of Persia: Sands of Time, it's one of the very, very few games I've beaten and gone back to play through again, simply because I enjoyed it so much. Actually, I can't think of a single other game I've done that with (except for going back years later because I have fond memories of the game). I haven't played the two after it yet.
The GTA games are fun of course (are they legal in Utah?), and you have all the EA sports games. Of those, I think the Madden, Fifa, and NBA Streets (think NBA Jam) games are best.