The only operating systems that support terminial services are XP pro, 2000 server, 2003 server. However, it is possible to install it on 2000 professional but it not asvised.
There is a program called ntswitch. It will make some registry changes that will allow you to use terminial servcies. Run it, reboot, reinstall SP4, reboot, install Terminal Services, reboot again. Also, you will need to open port 3389 on any firewalls or forward port 3389 to your IP from any routers.
Go here to download it.
http://www.xcopy32.com/downloads/hacks/