How do I remove a hotfix that won't install??

Can somebody help? I have XP with SP2 installed however auto update has
downloaded a hotfix (KB885626) which I don't think I need, as this provides a
fix before the installation of SP2. Now when I try to apply the hotfix, the
machine hangs and I have to power off. Also add/remove shows the update as
having already been applied!! What I want to do is delete the download from
the list of fixs to be applied, but I can't find where in the registry the
list is maintained! Any solutions??

Regards
Graham