I came in contact with a Windows Media Center PC only recently, specifically with Microsoft’s Windows XP Media Center Edition 2005. I noticed that it did not recognize DVDs that were stored on the hard drive of the computer which was kinda odd for a Media Center.
Well a little research revealed a Registry setting that would enable the option to enable the DVD library in Windows Media Center 2005. That DVD Library can store the DVDs that are stored on the hard drive in a Video_TS folder.
Here are the steps that are needed to enable the DVD Library feature. Exit the Media Center application and start the Windows Registry Editor by using the shortcut Windows R, regedit, enter.

Now navigate to the Registry key HKEY_CURRENT_USER \Software \Microsoft \Windows \CurrentVersion \Media Center \Settings \DvdSettings and edit the value ShowGallery. Change the value from Play to Gallery.

Control Windows Media Center with Keyboard Shortcuts
Before I edit the registry, does anyone know if this works in Vista Media Center? Thanks in advance.
bump
Yes, Ive done it on my laptop and pc both have vista. My only problem is getting my xbox360 to see it.
I did the reg edit as per MS web site and it doesn’t work. However, I did notice something on my mce server station (not my xbox).. when you go to the folder where a dvr-ms (I converted a VOB file with VideoReDO to dvr-ms) file is stored (it has the mce icon)and you open the file it opens mce and the files starts to play then I stop it from playing and go back to the main mce menu, I then can see the “DVD Library” option, but when I close MCE and reopen without opening the file just opneing MCE, it dissapears!!!! Grrrrr.
my windows media wont let me play movies