Thanks for all the help so far.
Just a few more things.
I compressed the original HD file in compressor using H.264.
Then set all the settings in DVD studio to HD-DVD. However, when I put the burned disc into, say, a computer, the native window size is 480. It’s the size of a normal dvd is that irrelevant or is it not HD?
Also, for the films we’ll be showing we might have 2-3 HD films and about a dozen or so SD films, they need to be shown in one linear presentation, but if we were to put them all on a regular DVD burned as an HDDVD then they would not all fit.
Any ideas?