Vista reduced functionality mode and Malware

[Rakel]

I have Windows Vista Business on my laptop.
This is a legal version. I suddenly noticed some websites to be unreachable notably everything microsoft.com

I have run Malwarebytes in safe mode to fix this problem.

But now when I logon I get "Not allowed change occured in Windows" I can click on "more information online" and that opens the browser so I can start
explorer or the command prompt.

But microsoft.com is still blocked so I can't fix it?

EDIT: It's probably caused by virus. (see second post)

[Rakel]

There are no system restore points.
Microsoft worked in safe mode, validation failed because of the changes made to the license.
The website tells me to run "net start slsvc", but this does not work in safe mode. ad-aware only found some cookies.
OneCare live reports hundreds (1267 items, 1 problem); the problem goes by the name of Win32/Virut.BM
But again, while OneCare finds it, it can't fix it in safe mode.

Can you please point me to an antivirus/antimalware that works?, One that can remove Win32/Virut ?

(I'm guessing the virus infected a system file.)
If I really really have to reformat, is it safe to back up my files, or will I infect myself again?
Never mind that I got rid of the viruses, yay. (just mcAfee in safe mode worked this time., got Virut and "New Poly win32")
If no one can help me here, that's not a enormous disaster, I'll going to the helpdesk next week.

Anyway, net start slsvc works in normal mode, but it doesn't help validation.
I'd try Repair with a Vista install disc, but I have no such disc.