I have a terminal server and for some reason, it restarts on trying to print some specific documents from CrystalReports XI.

The minidump blames win32k.sys (tho im not expert on reading it), but i don't beleave it... i think its a printer driver - jet i cannot test it because sometimes it prints fine and i have many printers.

It's this MS KB: h t t p://support.microsoft.com/kb/911028/en-us
But i already have the SP2 on my Win 2003 x64 R2 - so i have no clue how to fix the issue.

I have the same problem:
Terminal Server Windows 2003 Std. R2 x64 with SP2.
Randomly crashes with crash:

STOP 0x00000050 (parameter1, parameter2, parameter3, parameter4)
PAGE_FAULT_IN_NONPAGED_AREA

The crash blames win32k.sys.
I performed a crash debug using windbg and I see also Winword.exe being referenced under "PROCESS_NAME". I think there might a problem with win32 applications running on a x64 Windows Server with Terminal Services enabled.
Did you try to analyse the minidump?
Good bye, let me know
Simone