User Permissions???

I recently upgraded from Windows 2000 Professional to Windows XP Professional and under the user permissions it only gives me “Limited” or “Administrator”. Now I am not running a Domain but I am on a rather large workgroup with anywhere from 15-50 hosts at a given time. I am not running any servers as of yet but I would like to limit the users ability with a little more than just the 2 options. Does anyone know how to set up WinXP so that I can get the same kind of User permissions options thatyou would get in Win2K.

Thanx in Advance