My partner's MBA (2,1, 1.6GHZ, 2GB RAM) keeps freezing up. This never happened before Snow Leopard was installed a couple of months ago, but it seems to be getting worse. It's not flash or youtube, it often happens when she's just reading email in mail.app or typing a document. She's an extremely light user - email, Office, Facebook, and that's more or less it. Sometimes the mouse will become all jerky and uncontrollable. Windows and applications freeze. Sometimes windows freeze but the mouse is still useable. Program switching takes several minutes to happen, and text entry fields freeze. Activity Monitor shows CPU usage is low, and there's over a gig of RAM free and half the HDD is empty. Temperature Monitor shows both cores around 50C. To be honest, I'm stumped. Any ideas?