I think I've stumbled upon a good way of doing it. Here's my current plan:
Rip the DVD video to either a single .mpg file or to separate m2v and audio files. Import the video into premiere using the mainconcept MPEG plugin which allows me to edit in premiere with the raw mp2 files from the DVD. I was going to use the Womble program, as
ReverendBeastly suggested, but it looks like the mainconcept plugin will allow me to do he same thing in Premiere. I'm going to be attempting some advanced things, like adding my own CG, and already knowing premiere will make my life easier.
Here's another question for you. When I'm done I want to make both DVD and Divx/xvid versions. What's the best way of going from Premiere to divx? I can export mp2 straight from the timeline for the DVD. I know I can then just re-rip the fanedited DVD to divx, but is there a way to save a generation, and go straight from premiere to divx? I don't really want to export from premiere as DV AVI and then encode that file. The DV AVI will be huuuge, and I'll probably screw up some field/aspect ratio/frame rate setting.