I've always just burned either DTS or DD depending on what is available on the disk. What would happen if I re-author a DVD with both DTS and DD? Personally I like DTS better, but only one of my DVD players is connected to a receiver that will play DTS tracks. Is there a way to switch between audio formats without have a main menu on the DVD disc?
If you have both formats, you need the navigation in the menus to change. Menus are no problem with most programs. Deleting the extras will keep plenty of space. Using a good app like DVDCopy3 and Rebuilder is also good for video under higher compression.