Windows Media Center (New!) uses all the media files you already have on your computer and integrates it into an entertainment system. The same video and music files you use with Windows Media Player are available for use with Windows Media Center. For example, when you rip music to your computer, you can play it using Windows Media Player and Windows Media Center. You can choose either one, the preference is yours. As you navigate to a media area, you can select options to find the media you want, and then use the media specific commands and controls to view, play, or change the media files.
If you know the library and want to play all the media, click play all.
You can select Now Playing or Now Playing + Queue on the start screen to quickly access and play items in the queue, which is a custom list of all the media you want to play.