My laptop freezes when i try to play WoW.?

It happens a few seconds after i select a toon, and start to play. I cant do anything. I thought that it might be overheating so i shut it down and tried again the next morning. The computer was not hot at all and it still does it. This has never done it before, and ive been able to play for a couple hours at a time. It only freezes when i play WoW.