This is best done in Safe Mode > Advanced Search with Hidden Files checked so you can see them.

You really should update to IE 8 for security reasons. This presents a huge security hole! :o

Are you using Vista? You really do not need to run Windows Defender (WD) as resident (on all the time) as long as you have Avast, which is resident. You can keep WD as on-demand and when you need it you will have to update the definitions, but it really is a memory hog.
You may want to run the AVG Uninstaller just to make sure AVG didn’t leave remnants, as it has been known to do. Here is the AVG Uninstaller Tool: http://www.avg.com/us-en/download-tools, then reboot your machine.

You’re referring to the Avast Repair? Or Windows Repair?

If after doing the AVG Uninstaller and upgrading to IE8 does not help, then I suggest an uninstall and clean install of Avast:

  1. Save a copy of Avast and save it to your HDD:
    http://www.avast.com/download-software – all products
  2. Download the Avast Uninstall Utility http://files.avast.com/files/eng/aswclear6.exe and save it to your HDD.
  3. Disconnect from the Internet at this time.
  4. Go to Control Panel and uninstall Avast through Add/Remove Programs if possible and reboot.
  5. If Step 4 fails, boot into Safe Mode (hit F8 repeatedly) and run the Avast Uninstall Tool. Uninstall ALL previous versions of Avast one at a time and reboot in between each uninstall.
  6. Reboot.
  7. Install the newest version of Avast and reboot.
  8. Get Internet access and register your copy or add the license key for Free, Pro, or AIS.
  9. Update the Avast definitions.

Let me know if this fixes your problems. Thanks.