i don't think anyone will ever say there are absolutely no risks. The
patches are thoroughly tested and installed at Microsoft well before you see
them.
The risk that some people have seen might be a conflict with a program. This
should be extremely rare.
In the particular case of NT4 and W2K, they have been out for quite some
time. Actually, NT4 is out over 7 years now, and i believe it will not be
supported further into the future. It's ancient in the tech world.
The bigger risk in my opinion is not installing the security patch.
I hope this helps.
--
Thomas O'Grady,
Security Business Unit
Microsoft Corporation
This posting is provided "AS IS" with no warranties, and confers no rights.