When I am traveling home, I spend a lot of time waiting in trains and on the airport. In this time I am looking DVDs on my notebook. I am using Windows Vista Mediacenter for this.
Because the DVD drive consumes a lot of energy, I copy the DVDs to my harddisk (the ones that are not encrypted). That gives me the opportunity to insert a second battery into the DVD drive slot, which extends my battery lifetime to 6-7 hours.
To let Windows Vista Mediacenter display the DVD library, you have to make a registry change:
HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionMedia CenterSettingsDvdSettings –> Change ShowGallery value to Gallery
Then open your Mediacenter and you can find this: 
You can add a folder from your harddisk: 
Then you can see the subfolders as entry in the gallery: 
Have fun watching your movies for a loooong time without the battery consuming DVD drive!
Source: http://support.microsoft.com/kb/930526/en-us
Tags: Mediacenter, Windows Vista