CAL4M1TY on 17 August 2008
Virtua Tennis 3 (or any sports game not related to NFL really), Kameo has some decent 2 player action, Guitar Hero, Viva Pinata, Lego Star Wars and Indiana Jones.
Kind of a shame you don't have a HDD, because the best casual games are on XBLA.
I would not go passed the hardcore games either. I've known females that hate games that got into Halo 3, purely because it's such a thrill when they get a kill. Don't get stuff like Gears and Rainbow Six: Vegas because it'll be a little too uninviting, but don't think they won't like it just because it takes more then 5 minutes to understand how the game works.
