Hi,
Check the event logs in NT, you may have a drive going south. Have any SP's or security patchs been installed. If running TCPIP stack check that MTU is set correctly, some of the security patchs screw the MTU in NT.
Copy the DB to the workstation, delete DB from server then copy DB back to server from workstation. This sometimes fixes the slowness problem.
Regards
Regards N Mc Donald