Hi, I have a problem. It started first few months ago, sometimes when I watched movie for a long time it started lagging. It didn't happen very often. Than it started happening more often and then even dock started lagging and Dashboard, Exposé and other things. So I decided to reinstall computer but it didn't help. I was hoping that maybe it will stop after I install Snow Leopard but it just got much worse. Everything I do (even writing) is lagging, not to mention that I can't even watch movies or youtube videos. Even switching windows is a problem! I hope you guys will help me because I'm desperate and I don't know what else to do. MacBook is late 2007; 2 GHz Intel Core 2 Duo Do you think that if I take it to an Apple Store they will help me even tough it's after warranty? There are no Apple Stores in here but I am going to Scotland in a few days.