Super Meat Boy, Limbo and Capsized come to mind. (maybe Braid, I forget) While it's neat that it supports the 360 controller, it's pretty irritating that they support ONLY that pad if you want to use a controller. It seems pretty silly that they'd bother to port it to the PC, but then not support any other controllers. (especially considering that most are either dual shock ripoffs or have similar button layouts anyway)

Maybe SMB got patched to where it supports more than that, though, as there was talk of that. It's been a while since I played it. IIRC, I had to use an application that tricked your system into thinking your "lesser" gamepad was a 360 one.

As for driving cars in open world games with the mouse & keyboard, I've never found it to be a big deal. (GTA III, Vice City, GTAIV, Just Cause 2 [tho its cars sucked anyway], etc) It's not as smooth, but I still prefer the freedom of mouse look.

Anyway, you've gotten some helpful replies above & below. Good luck!