I vote Wii, but since that isn't an option I guess I'll go with umm both!

Reason: PS2 has Guitar Hero & Xbox has Oblivion -> yay for both!!!

If I really had to chose though, I think I'd go with PS2 (in fact I have one at home somewhere, but I didn't buy it myself ^^) PS2 can play DVD's and the controls are much better than Xbox