There isn't, really. Both use rdp (Remote Desktop Protocol). In W2K,
it was called Terminal Services, in XP Remote Desktop, and in Windows
2003 you have both.
What was called "Remote Administration mode" in Windows 2000 Terminal
Services is now called "Remote Desktop for Administration" in Windows
2003 (allowing 2 concurrent connections + 1 console connection).
The "Application Server mode" of Windows 2000 Terminal Services is
now called plainly "Terminal Services" on Windows 2003 (unlimited
number of connections).
