how to remove unaccessable programs from registry

Hi, was wondering if someone could help me here. The problem is I have all my clean up programs d/led on an external drive that I can no longer access. I've posted about it and no one answered so i've tried to reinstall the programs on the C drive and get an error saying I have to uninstall the program first before I can install them again. I can't uninstall them because the E drive is not working. GRRRR...... Here it the other post http://forums.majorgeeks.com/showthread.php?t=76243
I think I now have to remove them from the registry but I have no idea if I am right or how to do that. Can someone please help me with this? I'm on a Dell computer with windows 2000 pro.
Thanks,Danu

 

if you know the names of the programs you can

go to run
type in
regedit

open edit, click find

type in the name of the program

when it comes up, right click and delete