Set file association for windows update?

Yesterday, I was just playing around with Vista when I thought that it's been a while since I've had any updates. I went into my control panel and clicked on Windows Update, but nothing happened. I right clicked on it and all that came up was create shortcut. So I went to the windows update site, and this box popped up:

::21ec2020-3aea-1069-a2dd-08002b30309d}\::36eef7dp-88ad-4e81-ad49-0e313f0c3...

This file does not have a program associated with it for performing this action. Create an association in the Set Associations control panel.

I went to the set associations control panel, but I really don't know what to do from there. I attempted to try some other fixes which include: methods 2 and 3 of the windows update reset and repair guide on this forum, scf/scannow or whatever it is in command prompt, installing sp2 beta. I spent a good five hours last night trying to fix this.

Some other information:
When I registered some dll's some were missing so I downloaded those. When I click on windows update in all programs it seems like it loads for a few seconds then nothing happens. When I click on wuapp.exe, that error message pops up from before.

Anyone know how to fix this? I'm running Vista Home Premium on a Dell XPS M1530
Thanks in advance!!!!