I just posted "How to convert a HD-DVD to an AVI" this was the winner in my various experiments to get HD-DVD content to work so I can shelf the drive since I will not be able to get new content on this media format.
All of the goals and caveats of that post apply here as-well, the first steps are the same, the last steps are the only ones that change.
- Demux the HD-DVD into its elementary streams using EVODMUX.
- Convert the VC-1 elementary stream from the HD-DVD 29.97 fps streams with pulldown flags to 23.976 fps progressive using vc1conv.
- Transcode the DD+ audio stream to regular AC3 using eac3to.
- Remux the VC-1 elementary stream and the AC3 stream into a M2TS (AVCHD) or TS using TSMuxR.
The resulting file was playable with ffmpeg\ffplay, I could also import this file with Handbrake (who by the way is a great tool, but don't ever venture into their forums the authors are hostile at best).
I suspect with additional codecs it would have played in WMP and Media Center also but I really did not want to need additional codecs for this to all work.