Does it start in SafeMode? If you get it started there, try to do a restore to a date before the issue. If you can't start Windows even in SafeMode, you'd need to by a Windows 7 disk to re-install it. You may want to get a new hard-drive as well, and keep your current one with all your files to copy over and as a back up.http://windows.microsoft.com/en-US/windows7/help/videos/fixing-a-problem-using-system-restore
Hi, Thanks for your reply. No, it won't start in safe mode. It won't start in any mode. I have purchased Windows 7 online (OEM system builder pack.) It was cheaper than at the store. I have read several things on how to install it. Any advice on the best way to do this?