MOSS CU / service pack versions

To check SharePoint version open central administration site--> Operations--> Servers in Farm

if your version is more than 12.0.0.6421 then it is SP2

12.0.0.6548 WSS 3.0 or MOSS 2007¹ SP2 + Oct 10 cumulative Update (KB2412268 + KB2412267)
12.0.0.6545 WSS 3.0 or MOSS 2007¹ SP2 + Aug 10 cumulative Update (KB2276474 + KB2276472)
12.0.0.6539 WSS 3.0 or MOSS 2007¹ SP2 + June 10 cumulative Update (KB983311 + KB983310)
12.0.0.6535 WSS 3.0 or MOSS 2007¹ SP2 + April 10 cumulative Update (KB981043 + KB981042)
12.0.0.6529 WSS 3.0 or MOSS 2007¹ SP2 + February 10 cumulative Update (KB978396 + KB978395)
12.0.0.6524 WSS 3.0 or MOSS 2007¹ SP2 + December 09 cumulative Update (KB977027 + KB977026)
12.0.0.6520 WSS 3.0 or MOSS 2007¹ SP2 + October 09 cumulative Update (KB974989 + KB974988)
12.0.0.6514 WSS 3.0 or MOSS 2007¹ SP2 + August 09 cumulative Update (KB973400 + KB973399)
12.0.0.6510 WSS 3.0 or MOSS 2007¹ SP2 + June 09 cumulative Update (KB971538 + KB971537)
12.0.0.6504 WSS 3.0 or MOSS 2007¹ SP2 + April 09 cumulative Update (KB968850 + KB968851)
12.0.0.6421 WSS 3.0 or MOSS 2007¹ SP2 (KB953338 + KB953334)
[Updated 1st Aug 09: SP2 download now includes the hotfix (KB971620) that corrects the activation issue more information on the Microsoft SharePoint team blog]

 If you are running SP1 after 13/Jul/2010 then you are running an un-supported environment,

12.0.0.6341 WSS 3.0 or MOSS 2007¹ February 09 cumulative Update (KB961755 + KB961756)
12.0.0.6335 WSS 3.0 or MOSS 2007¹ December 08 cumulative Update (KB960010 + KB960011)
12.0.0.6331 WSS 3.0 or MOSS 2007¹ October 08 cumulative Update (KB957691 + KB957693,KB958567 and KB958569)
12.0.0.6327 WSS 3.0 or MOSS 2007¹ August 08 cumulative update (KB956056 & KB956057)
12.0.0.6318 WSS 3.0 or MOSS 2007¹ Infrastructure Update (KB951695 & KB951297)
12.0.0.6303 WSS 3.0 or MOSS 2007¹ post-SP1 hotfix (KB948945)
12.0.0.6301 WSS 3.0 or MOSS 2007¹ post-SP1 hotfix (KB941274)
12.0.0.6300 WSS 3.0 or MOSS 2007¹ post-SP1 hotfix (KB941422)

12.0.0.6219 WSS 3.0 or MOSS 2007¹ SP1
12.0.0.6039 WSS 3.0 or MOSS 2007¹ October public update
12.0.0.6036 WSS 3.0 or MOSS 2007¹ August 24, 07 hotfix package
12.0.0.4518 WSS 3.0 or MOSS 2007¹ RTM