I'm having trouble with DVD Playback in Media Center. This is actually a problem that I was experiencing in Vista, too.
Here's the problem: Basically every time I put a DVD in and click play, the first few seconds of the playback are choppy and sluggish. But then it is suddenly fine and will play the rest of the DVD (or episode on the DVD) just fine. This problem was occuring in Vista ed. of Media Center, as well.
I've looked around, and folks have said that this might be associated with my Graphics Card.
Here's my relevant system info:
CPU = i7
Ram = 6GB tri channel
GPU = 512mb ATI Radeon HD 4600 series
Video out is carried by HDMI to a HD TV.
Resolution is at 1920x1080 and is controlled in Catalyst Control Center
(Moderators Please Note: I'm going to put this post in the Media Center forum, as well. I'm not sure if this is a violation, so please let me know and don't be mad if it is.)