Managing Terminal Server Remote Admin Mode on Windows 2K Server

I have some users that connect to my Windows 2000 server from their homes using Terminal Services in Remote Administration mode. The users only need to run one application on the server. To get this to work I had to give all of the users full admin rights, which as you can imagine is not a good idea.
My question is this: Can I manage these Terminal Services users on the server so they can only run this one application (no shutdown, no internet, ect) running remote administration mode or do I need to buy Terminal Services Application Server licenses?
Thanks for the help.

Tim