First thing to check with a laptop is always whether it is over heating. Many laptops will admit a beep when overheating and then shut down. Prop the laptop up about 3 inches and have any household fan blowing towards the rear of the laptop while you try again. If that does not fix the problem, then yes windows is likely corrupted and you must run a repair. To do this insert the windows disk or recovery disk into the machine and continuously press any button such as [space] to get into the disk loading screen where you should follow the directions until you get to the point where you can hit repair. Have the disk scan your operating systems for errors and hopefully fix them. Since this rarely works you might then need to reinstall windows.