Halo
Prince of Persia
Project Gothem Racing 2
Beyond Good and Evil
SSX 3
Rainbow Six 3(the online CoOp with friends OWNS)
Crimson Skies(dogfighting rocks online once you play through the single player for plane upgrades)
Top Spin Tennis
Armed and Dangerous
if you own and xbox and have a broad band connection, you best go out and get yourself XBOX LIVE if you haven't already...it is 100% worth the 50 to 70 bucks you pay for it(50 with no game, 70 with mech assault)
Just find out what your own top 10 are, heh. Love this service!(yes, I still love it even though I'm in the SE and it takes a while to get here and back)
Project Gotham 2 is a great game
I also play Links and Top Spin on Live, both are awesome games. Since you prefer driving and sports in particular, those are good choices to go with the standard football/basketball/hockey sports choices (all of which I prefer the Sega versions over the EA ones but both are excellent brands).