I got a virus that pretended to be antivirus software. I shut down and booted in safemode and ran superantispyware which seemed to remove all of the virus applications, but it resulted in an inability to open executable files or any other programs. When I attempt to, I get a prompt to select an application to open the program with. The fix says to import Windows Registry Editor Version 5.0 How do I copy this text file?
More aboutwindows registry editor version
Try booting from your Windows 7 CD and selecting the option to repair a Windows installation.