I know this is a late response, but FWIW there is essentially no difference in WinNT server-vs-workstation.

In NT 3.51 there was 1 Registry change to mark the difference between OS's. In 4.0 I think there were 5-6. I don't know many are in NT5 (Win2K) or NT6 (XP), but I bet the number is still low. WinNT is WinNT, the Registry changes just tell (1) the OS how to technically behave with allocating threads and etc and (2) the OS how to administratively behave with licensing issues. Server is essentially Workstation/Professional without hard limits.

Kind of like how MSDE is MSSQL with hard limits but all of the functions are the same. It would be doubly (triply?) expensive for MS to fork complex code like the OS or database, so they just add layers on top the core to make it behave different.