Oblivion is great, but get the Game of the Year edition, and it has $40 of DLC with it, unless you find regular Oblivion for REALLY cheap. Kameo is definitely worth the $20 or so, if you are interested in it, you should like it. Guitar Hero 2 also, it is really really fun, and can have good local co-op/versus.
As for EDF, I don't have it, but if you want it, it should be $25 at WalMart, because it is not a YMMV situation. Also, it seems like you have a lot of single player games, but you should really get Xbox Live to fully enjoy Gears, and you can get XBL Arcade games too!