Also, in case it's helpful, here's the output from a set command on the system I'm working on:

COMPUTERNAME=TEST9837545
ComSpec=C:\WINNT\system32\cmd.exe
NUMBER_OF_PROCESSORS=1
OS=Windows_NT
Os2LibPath=C:\WINNT\system32\os2\dll;
Path=C:\WINNT\system32;C:\WINNT;C:\WINNT\System32\WBEM
PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
PROCESSOR_ARCHITECTURE=x86
PROCESSOR_IDENTIFIER=x86 Family 6 Model 5 Stepping 2, GenuineIntel
PROCESSOR_LEVEL=6
PROCESSOR_REVISION=0502
PROMPT=$P$G
SystemDrive=C:
SystemRoot=C:\WINNT
USERPROFILE=C:\WINNT\Profiles\Default User
windir=C:\WINNT

I'm getting to it (right now) using PsExec, hence the Default User stuff above.