For the giant filesizes from Vegas it sounds like you're rendering an uncompressed .avi, that's why it's so huge. That'd be my guess anyway. Are you sure you've tried divx/xvid encoded .avi's? I think they should play, but I've never actually used a divx player. Drop your video file into
GSpot and see what it says there.
When I make dvds I usually use a program called
ConvertXtoDVD. It's not free, but it's a really great piece of software in my opinion. That isn't going to make it a divx thing though. It takes whatever you put in, (it recognizes most codecs and containers), and just converts it to a standard dvd compatible mpeg2. I don't know if that will work on a pure divx player, (do they make those anymore?), but if it's a divx compatible DVD player it should work.