I nearly went crazy trying to find an answer to the same problem. I tried everything, but when I read somewhere here that someone had saved the uninstall to their computer, I realized that even though I never downloaded anything from the Internet, I did have the program disk. I hope you do, too. What I did was this:
Click on Start \ Control Panel \ Add New Programs
Insert the CD belonging to the program that you wish to delete and click on Add a Program from a CD or a Floppy (or something similar to this if you don't have Windows XP Professional.
When I did that, the program on the CD came up and asked me whether I wanted to Modify, Repair or Remove the program. I clicked on Remove, of course, and the program was completely removed.
Good luck. And thanks to the other person who helped me figure out what I could do since I didn't have any installation program saved on my computer (I didn't have to have it, though, because I had the disk).
