That looks like it can't write to the HKEY_CLASSES_ROOT section of the registry.
The only thing I can think of that would prevent writing to the registry is trying to install when your account doesn't allow it. Do you have administrator privileges on this computer?
Other than that? I guess a really badly corrputed Windows installation might prevent a Registry key from being created...but I've never seen that happen.
I am also told that I have had similar problems on this home computer of mine with roxio easy cd creator and video wave. Same problem I think. they're corrupted. Can that have anything to do with it?
In the Control Panel there is a "User Account" applet. That'll show what sort of account you have. If it doesn't say "Computer Administrator", that'll be the problem.
If it's a bad installation...try reapplying the latest service pack (SP2). I always try that before reinstalling Windows. If that doesn't work...oy. Pop the CD in and reboot and choose to repair the installation.
Last reosrt: and actual reinstallation of Windows. Hopefully, you won't have to. If you do have to, use the Trasnfer wizard to save all your settings somewhere. That'll make it slightly less painful.