Yes,
This is possible but under certain conditions.
If the Advanced server is in Application server mode and you have enabled use remote control under the administrative tools terminal services configuration and use interact with session.
for winxp pro use the remote desktop client that comes with it and on win2000 just download and install msrdpclient for winxp. there is one other tab to enable remote control under each clients security profile under manage computer local users and groups or under the active directory users and computers. right click the account and choose properties look for the remote control tab and enable i uncheck the require user permission and check off interact with session. now you can interact with that session from the server provided you are a administrator of course. it work just like vnc viewer or pcanywhere but it is built in. i have only had 1 client pc that the graphics mode of the user was not compatible with this so it should work for you.