PROBLEM: Performance on Windows 2003 with Citrix Presentation server is not optimal.
SOLUTION: The following registry keys (from Microsoft) will improve the performance on your Terminal Server:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Configuration Manager]
Disclaimer: As with everything else at Cool Solutions, this content is definitely not supported by Novell (so don't even think of calling Support if you try something and it blows up).
It was contributed by a community member and is published "as is." It seems to have worked for at least one person, and might work for you. But please be sure to test, test, test before you do anything drastic with it.