As a movie tie-in AND a kids' game, you'd think that Cars would be a god-awful blight on humanity. But, in fact, it's actually pretty decent. It's a good, solid racer that captures the charm of the film perfectly. It's not revolutionary, it's not amazingly super-fantastical, but, at the very least, it's fun, and at 13 quid, you can't really go wrong.
Oh, and did I mention it has easy achievements?