Windows Installer keeps trying to re-install software that is already installed

I had this problem before, but couldn't find a solution, so I just put up with it, but now I'm hoping I can find a solution.

I'm running Windows XP. I recently had a virus problem, and the local computer repair shop couldn't get rid of it, so they wiped the hard drive and re-installed Windows.

Before the wipe, I had MS Office installed, but it was a student edition, and since I'm no longer in school, I doubt I would be able to re-install from my Office CDs. But after the wipe, I was looking through the programs that were included with Windows, and I saw Office listed. So I tried opening Word to see what happened. It started installing, but then a window popped up saying it was a trial version.

I didn't want to deal with a trial version that would run out anyway, so I cancelled the install. That's what seems to have messed up Windows Installer.

I tried to un-install Office, but that hasn't helped. Whenever I reboot, or use my Acrobat Firefox plugin to save a web page as a PDF, Windows Installer pops up and tries to re-install Marvel Comic Book Creator. I have to click Cancel multiple times to make it stop.

When this happened before the wipe, what started it was something similar. I downloaded some free software, then I changed my mind, so cancelled the install and that started the same Windows Installer problem.
At that time, I tried to solve the problem by un-installing the software it was trying to re-install. But then, Windows Installer just moved on down the list and tried to re-install my Sonic CD/DVD burner software.

How can I fix Windows Installer? Or if I need to re-install it, how is that done? I have some System Restore disks, but I don't know how to use them, especially when I'm really only interested in restoring just the one program.
Thanks!

 

Hey buddy, try uninstalling the program you need gone with this, http://www.majorgeeks.com/files/details/revo_uninstaller.html, then search for leftover files with this, http://www.majorgeeks.com/files/details/everything.html, then go to My Documents, then Downloads and remove the programs installer, and see if that helps.