You can convert a flash movie to a Quicktime file. This can
then be converted to the right mpeg format for recording on a DVD.
Preserving the quality is a matter of the original
resolution. By definition you can't fully preserve quality because
both quicktime and mpeg are compressed formats, but I would say by
using the right parameters you can keep the quality loss invisible
to the naked eye.
However, you will loose *all* of the interactivity. If you
think you can create a DVD menu system using Flash, no