That depends on what kind of quicktime movie you want to compress. I would edit your program in full resolution, then export your movie to dedicated compression software (like cleaner or sorensen squeeze, where you can then deinterlace and correct the aspect ratio (square vs non square pixels) and then the movie will be suitable for viewing on a computer monitor. the movie will then be small enough (depending on compression) to email, or stream on the web.
If you want a ‘no fields’ DVD, you can take your export your finished movie into After Effects, interpret the footage as having no fields, render out a new movie as having no fields and then you should be all set.
Do you expect people to watch this DVD on their computers and not television sets?
Hope this helps.
Jeremy