locating windows server 2003 running r2 is a bit of an obscure value. with windows server 2008, you can simply check the build number. unfortunately, in 2003, it's a little more hidden. here's a couple of ways of getting the information.
in configmgr, one place the information is contained is in the view v_gs_operating_system in the name0 column:
select sys.Name0, os.Name0
from v_r_system sys
inner join v_GS_OPERATING_SYSTEM os on os.ResourceID = sys.ResourceID
where os.Name0 like '%2003%R2%'
order by sys.Name0
in wmi, the information is stored in win32_operatingsystem in the attribute "OtherTypeDescription" as indicated here in this msdn article.
Data type: string
Access type: Read-only
Additional description for the current operating system version.
Windows Server 2003 R2: Contains the string "R2".
Windows Server 2003, Windows XP, Windows 2000, and Windows NT 4.0: OtherTypeDescription is null.
you could use a powershell command like this to check a server:
Get-WmiObject -ComputerName myComputer -Class win32_operatingsystem | fl __server, caption, othertypedescription
resulting in this:
__SERVER : myComputer
caption : Microsoft(R) Windows(R) Server 2003 Standard x64 Edition
othertypedescription : R2
thanks erik and chip. :)