Oh infected by Sujin Virus??
Download Sujin Virus Remover:
*rapidshare.com/files/80822125/Sujin.com.np_Remover.rar.html
And well, you haven't messed up with the registry, some other virus has, which must have put a shutdown command in your startup script....
Try opening in safe mode and if you are successful, just Post your HijackThis log here...