These are the settings recommended when importing media into iDVD. They are the same settings that iMovie uses when exporting it's data for use in iDVD.
| Video settings | Apple Intermediate Codec (25fps PAL, 29.97fps NTSC) |
| Recommended size | 960 x 540 (PAL), 796 x 480 (NTSC) |
|
Audio settings |
AAC, 2ch Stereo (PCM is fine as well) |
You've got to decide your aspect ratio for your iDVD project. 16:9 is the way most people will go.

The best result will be achieved if you match the capture area, output movie size. In iShowU HD, there are presets for iMovie that will work well with iDVD.
This will result in minimal (none!) scaling of the final video. We've also captured full screen Apple Animation into iDVD 08, and it came out fine. Well, where "fine" means we could make out what was on screen. Some people would have though the quality was "bad", because the content had to be scaled. It all depends on what it is your capturing. If you're capturing video, then scaling isn't that much of an issue. If you're capturing text and you want people to be able to read the desktop icon labels, menus and so on then you'll need to be mindful of scaling issues.
For the best visual result, set the capture area to 796x480 (NTSC) or 956x576 (PAL). In these two cases we're recommending a a 16:9 ratio.
To ensure good quality, make sure you use a codec with minimal compression (Apple Intermediate, Apple Animation) The reason being that iDVD will need to encode and compress your imported video to MPEG-2 format for playback on DVD players. You wouldn't want to use a heavy compression codec such as H.264 or MPEG-4 and then import to iDVD to convert the video to MPEG-2 as this might cause undesirable results (see the section in General Advice regarding compressing twice).
Shooting Digital has an interesting article about feeding iDVD stills. It's all (again!) related to scaling and the artifacts that can be introduced.