Okay, I'm a new xBot for about a month now. The game I enjoy playing the most is CoD2--and I don't eveni like playing FPS's! I say you should get CoD2. The action in single player is amazing, the music is great, the presentation is great. And yesterday I just hooked up to XBLive and had a fantastic experience.
PGR2 isn't my cup of tea. Another genre I don't enjoy too much is racing. The only racing games I enjoy is Burnout and Mario Kart :-D
PGR2 is just too real for me to enjoy. I can't control a car for the life of me.
My favorite game right now however, is Simpson's Hit & Run. It plays beautifully on the 360 and in widescreen. I only rented it once, but since it was so cheap it's worth buying. The graphics don't even bother me, maybe since going from cartoon to 3D amazes me so much.