What is the highst quality exporting format? What is best if you intend to burn to dvds (and still have them work in average dvd players)?

MPEG-2 is the DVD format.  So, you will need to get your sequence out as a MPEG-2.  I generally keep the bit rate between 4000 and 6000.

Standard AXP does not support MPEG2 export as far as I know.

Most of us export Quicktime reference (supposed to be a lossless format) and then use a different program to encode and burn DVD.

Klil:

Most of us export Quicktime reference (supposed to be a lossless format)

For video there's no "supposed to be" about it.  Quicktime reference has that name because it consists of nothing more than a series of pointers to the original video media.  Because it's doing nothing to the actual material that it references, it must, by definition, be no more nor less lossy than the original media.

Because QTref is designed to work with video only, for audio the situation is different.  Losses are possible.  Any audio component will be exported as a mixdown and re-encoded, and automatically dynamically linked to the QTref for playback.  If the audio codec used is lossy or at a different sample rate or bit depth to your original sound the end result can be degraded.

pagerussell:

What is the highst quality exporting format? What is best if you intend to burn to dvds (and still have them work in average dvd players)?

Workflow

Export QTref from Avid

Import QTref into an Encoder and encode to MPEG 2

Import MPEG 2 into a DVD authoring application and create a DVD

Burn the DVD image/files and pray it plays

The above should give you more then enough pointers to search this site and the internet to get the picture complete.

Menno