Were you trying to reencode pal to ntsc? Cos I found out that regarding the picture, pal dvds do have all the footage intact in the vobs, it's just that there's a command to play them at 25fps.
If you demux, and make a mkv that plays the footage at 23,976 fps, it wlll play flawlessly. You just need to remux the ntsc audio (with the correct speed), or transcode the pal audio back to 23,976, to have mini-hd files of your fave movies that plays on any HD TV.