I know it's a little confusing but Windows XP is also known as Windows 2002 and Windows v5.1 so what is displayed in "My Computer" refers to that version ;-)
The best way to check the version number of MCE is from the 10 foot interface in Settings -> General -> About Media Center which is described in this Microsoft Knowledge Base article.
Windows XP Media Center Edition:
- v5.1.2600.1106 - Release
- v5.1.2600.1142 - Hotfix KB815487
Windows XP Media Center Edition 2004:
- v5.1.2600.1217 - Release
- v5.1.2600.1321 - Hotfix KB830786
- v5.1.2600.2180 - Sevice Pack 2
Windows XP Media Center Edition 2005:
- v5.1.2700.2180 (xpsp_mce.040810-0205) - Release
- v5.1.2700.2230 (xpsp_mce_qfe(wmbla)) - Update Rollup 1
- v5.1.2700.2231 (xpsp_mce_qfe(wmbla)) - Update Rollup 1 (German Only)
- v5.1.2710.2732 (xpsp(wmbla).050805-1239) - Update Rollup 2
- v5.1.2715.2773 (xpsp(wmbla).051011-0745) - Update Rollup 2 + Hotfix KB908250
- v5.1.2715.2812 (xpsp(wmbla).051215-1116) - Update Rollup 2 + Hotfix KB912067 (January 2006 Update Rollup)
- v5.1.2715.2883 (xpsp(wmbla).060409-2023) - Update Rollup 2 + Hotfix KB914548 (April 2006 Update Rollup)
- v5.1.2715.2941 (xpsp(wmbla).060629-0920) - Update Rollup 2 + Hotfix KB919803 (July 2006 Update Rollup)
- v5.1.2715.3011 (xpsp(wmbla).061009-1511) - Update Rollup 2 + Hotfix KB925766 (October 2006 Update Rollup)
Windows Vista Media Center:
- v6.0.6000.16386 (vista_rtm.061101-2205) - Release
- v6.0.6000.16465 (vista_gdr.070407-1200) - Hotfix KB932818 (April 2007 Cumulative Update)
- v6.0.6000.16484 (vista_gdr.070509-1510) - Hotfix KB935652 (June 2007 Cumulative Update)
- v6.0.6000.16551 (vista_gdr.070828-1515) - Hotfix KB941229 (October 2007 Cumulative Update)
- v6.0.6000.16679 (vista_gdr.080422-1604)
- v6.0.6000.20670 (vista_ldr.070828-1515) - Reliability Update KB941649
- v6.0.6000.20750 (vista_ldr.080109-1510) - Hotfix KB947172 (February 2008 Cumalative Update)
- v6.0.6001.18000 (longhorn_rtm.080118-1840) - Service Pack 1
- v6.1.1000.18273 (longhorn_mc_dev.(wmbla).080702-2208) - Media Center TV Pack 2008 KB953272
Note: The version information also includes the build date (which I don't know for MCE pre 2005) e.g 051011 was compiled on 11th Oct 2005 at 07:45.
Mark Salloway has a further run down on the various version numbers on his blog at: http://www.salloway.org.uk/MediaCenter/2004/version.htm
Steve
My Media Center SetupMedia Center Version Info