The name of the game is -
- Don't install anything you don't NEED
- Disable any services you don't NEED
- If a service is required, if possible - have it startup MANUALLY instead of AUTOMATICALLY.
Which services are absolutely necessary depends on the OS and on what all you plan to do with the machine. Black Viper has good info on services required in
Windows 2K Services and
Windows XP Services, but not (unfortunately) for NT. Never the less 2K is based on NT, so
Windows 2K Services would be a good place to start.
If you don't need to connect the machine to the internet, there is less to be installed (anti-virus scans are only required on machine you do downloads from) and there are more services you can turn off.
When you think you are done, download
an older version of SysInternals Process Explorer that will run on Windows NT and run it on your dedicated MAME machine. Google the executable name.exe of each running process; figure out what it is and if you really NEED it.
Good luck.