|It might be easier to clean it up yourself--uninstall software you've added, run Ccleaner and something like malwarebytes. Delete files you've added to My Documents and in other folders that may have personal information.|
If you do a format and reinstall you mentioned upgrading to IE 8. Google these files for download links:
The first is the installation file for IE 8 for XP. The second is a cumulative update for IE 8 on XP. The third is an update they deemed so critical they reopened IE 8 for XP support just to add it.