by ronallandottk on Tue Jun 16, 2009 3:12 pm
Simply put, it appears as your PC is suffering from a corrupted registry.
Before anything else, try pressing F12 while your PC is booting, and see if it enters the boot menu. Try selecting "last known good configuration" and see if the boot is successful.
If not, the corruption may be beyond what Windows can restore.
There is a way to repair a system with a corrupt registry. The procedure is detailed in the following Microsoft support article:
http://support.microsoft.com/kb/307545
It's a little tedious though, but it will fix your PC if you really have to get it going again.
Personally, if there wasn't any important data that I have to recover, I'd rather just do a clean reformat and reinstall Windows. It would at least give me an opportunity to get rid of the all the junk from installed/uninstalled programs, null registry entries, orphaned files/folders/DLLs, etc.