WIndows NT station slowdown, argh!

Mar 30 15:36 UTC 2000

THe problem:  I have a Windows NT 4.0 computer with SP3 that is slowing
down in odd locations, like any time you right-click on something, and the
apps are starting to get twitchy about starting up.  Normally, I would
delete the user data files (not personal data, the NT settings files) and
that usually clears the problem.  The issue this time is that ALL users
accessing the machine have the problem, so the settings files are less
likely to be the cause.

Any ideas?  (Short of standard solution #1.)