Anybody else besides apprentice who reads this, maks sure you are aware of what your doing before following anything I say!
The easiest way I know of to perminantly disable any service is to point windows to the wrong location for the DLL. You could try to delete or modify the DLL, but next time you insert the windows cd, or if you have the service pack install files still on your computer, it will restore the first microsoft signed dll it can find.
The windows registry stores the dll location of the windows update service in this key, under the value name "ServiceDLL":
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\wuauserv\Parameters
Just change that value to something invalid, and the service wont ever start itself anymore :happy:
You can also do the same thing to the help service, which always re-enables itself everytime you use anything even relating to help files though not necessarily dependant on the help service, and imo is a waste of memory and has been the dependant of some pretty bad vulnerabilities, (namely the one where a URL link could cause IE to delete files in any directory). It's registry key is here:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\helpsvc\Parameters
Note this will also break some microsoft middleware diagnostic programs like the msinfo32 thingie (none of which I ever use).