Good luck. My guess is you will have to reformat and reinstall Windows 7. It's probably a corrupted file somewhere. When you reinstalled the latest IE, it should have fixed it. It wouldn't surprise me if a malware infection messed it up - even though the virus might be gone, the damage is done so to speak.
Another thing you might try is making a new user account, copying your personal folders over, and then deleting the corrupted account. That might fix the problem. Otherwise, I'd suggest reinstalling Windows entirely.