FYI:
Anyone that has a NOD32 anti-virus Remote Administration server set
up can produce a list of computers administered by the server. That
list can be exported as a csv file and it can include the operating
system retrieved by the anti-virus client software. The data are
available whether the clients are online or not. This method is not
dependent on the computers being part of a domain and it is not
dependent on Windows remote administration being enabled on the
client. I used a list from NOD32 Remote Administration to cross
reference the list of Windows XP computers that I retrieved from
Active Directory (the comparison was done by taking advantage of
findstr.exe /v /i /g).
The NOD32 Remote Administration database, similar to Active
Directory, retains computer names even after the hardware has been
decommissioned, so I had some cleanup to do in that list as well.
-Stefan