I suggest something completely else. Skyrim, played in First-Person perspective, fullfills my need for mindlessly killing anything that gets in my way. And there's still Call of Duty 2.
For racing games, try Forza Horizon 1. Gorgeous graphics, tight controls and a good soundtrack. And if you're bored of the same music over and over again, just stream OutRun tunes from your USB flash drive to your 360.
But don't even touch the shitty crippled port that calls itself Forza Horizon 2 on the 360.