OK, I couldn't wait and bought this DVD this afternoon. I read the disc using MyDVDedit and this reveals:

* The disc is not encrypted, which is unusual. And no Macrovision either.
* Coded for all regions except Region 7.
* The video format is PAL, Interlaced.
* The Aspect presentation is 16:9 Auto Pan & Scan. What this means is that on a 16:9 screen, all content is presented full frame. On a 4:3 screen, the sides will be chopped off (assuming your DVD player conforms with the DVD standard and respects the Disc setting for Aspect).
* All 4:3 clips are actually pre-encoded with "Pillarboxing" to make it 16:9 fullframe. This will cause a 25% reduction in horizontal resolution. All clips which were originally 4:3 Letterboxed have been cropped and scaled to make them 16:9 fullframe. This will cause slight blurriness.
* What this all means is that on a 16:9 screen, all content will appear as expected - 4:3 clips will have black pillarboxing, and 16:9 clips will fill the screen. However, on a 4:3 screen the "widescreen" clips will have their sides chopped off. This may annoy some viewers with 4:3 screens.
* There are 2 titles on the disc - one to play each clip and return to the menu, and one to play all clips one after the other.
* All clips have two audio tracks, both AC3. One is Stereo (2/0) and one is Surround (3/2).
* There is no hidden content on this disc. No hidden titles or chapters.

The only way to author a DVD with mixed-aspect ratio content and have it automatically present correctly on both 4:3 and 16:9 screens is to have each video clip as a separate "Title". The Aspect presentation setting can only be changed between Titles, it cannot be changed between chapters of the same title.

The 4:3 content needs to be pre-pillarboxed (as is done on this disc) and the Aspect presentation set to "16:9 auto pan&scan". On a 16:9 screen you see the pillarboxing, and on a 4:3 screen the pillarboxing would be chopped off and all you would see is the fullframe 4:3.

The 16:9 clips should have the Aspect presentation set to "16:9 auto letterbox". They present normally on 16:9 screens, but the clip would be automatically letterboxed if presented on a 4:3 screen.

So because this disc has all the content in one Title, the Aspect presentation setting is fixed for the entire disc, and the above cannot be done. Result: viewers on 4:3 screens will miss the sides of the 16:9 clips.

There you go. More than you ever wanted to know.

Mmmm sounds like Nathan needs to redo the DVD for all of us!

Hi Clipmagnet

Are you able to give me an email as I am hoping to ask you some questions regarding authoring DVD Titles, you sound like you know a lot.

Thankyou

Lee