GRID is really good, yes. And suited for your system. It's a good all-round racing game - including touring cars, GT, formulas (not F1) and others.
A really nice and compelling experiance. I remember enjoying the carreer mode very much.
I got Burnout Paradise Ultima edition for less that $10 on steam and my kids love it (I'm more of a L4D2 kinda guy). You just have to wait for the sales and you can get a lot of games for cheap on Steam.
You know there are many enthralling racing games are available now days. Among different type of games like First Person Shooter Games, Adventure Games, Puzzle Games, Action Games etc, Racing Games have a place of their own in the hearts of the gamers. To shine in these games you need to have a different type of competence and skill. Racing games are getting more and more demanding and complex with real simulation of driving environments and AI competitors. I would suggest the thrilling games like Need for speed Undercover, Burnout Paradise: The Ultimate Box, Moto GP 08, and MotorStorm: Pacific Rift PS3 and OutRun Online Arcade Xbox360.... Now get start on your Race...Cool