When you say “DVD”, do you mean SD or HD? If SD, I wouldn’t recommend an uprez and downrez for the process, but just go straight to an AVID JFIF codec. You can also import those directly and select uncompressed on the Avid side, avoiding any further compression if you have the room.
If you are looking to do an HD video DVD, you have to decide where the best uprez can be done quality wise from SD to HD. Boris has a good reputation with their plug-in or you can do this in After Effects with an uprez plug-in there and export DNxHD as your output format.
Michael
Michael Phillips