Um.... folks, there is no F8 or safe mode options under Windows NT 4.0. Micron, be careful who you listen to!
Sounds to me like you disabled the i8042prt.sys device driver, which is the PS/2 keyboard/mouse port driver.
If the machine boots, go to another machine on the network, start regedt32, connect to this machine's registry, change HKLM\System\CurrentControlSet\Services\i8042prt\Start back to 1.
If you can't do that, boot to the windows 2000/xp recovery console (yes, on an NT4 machine), log on and type:
ENABLE I8042PRT SERVICE_SYSTEM_START
Reboot and use your mouse and keyboard once again!
