I just had the same problem and first tried to remove the files using
Norton. .Didn't work. I then tried editing the registry but the
registry wasn't acsessable.
I then switched to Safe Mode and looked for the information to change
in the registry but couldn't find it.
Then also in Safe Mode I had no problem deleting the files that Norton
couldn't delete under Normal operation.
The files causing the problem were;
C:\WINDOWS\system32\svshost.exe is infected with Backdoor.SDBot.Gen
C:\WINDOWS\system32\zonealarm.exe is infected with W32.Spybot.Worm
They recommend to disable the System Restore to prevent the system to
be restored with the virus if they are in the registry.
In my case they weren't .
I have scanned the computer with the latest Norton Anti Virus
information and also remotely controlled by the Norton site and found
no problems.
Hope it helps
Vlad