i was just looking through the SERVERPROPERTY functions, and cannot seem to find anything that shows the operating system.
it is buried in @@VERSION, though, so i'd expect a serverproperty to pull that part out.
the last part of string from SELECT @@VERSION that you can re-translate into something that makes sense to you:
Win7= ...on Windows NT 5.2 (Build 3790: Service Pack 2)
Server 2008 = ...on Windows NT 6.1 <X64> (Build 7601: Service Pack 1) i think.
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