What Video Format has the best Quality (MPG, AVI, ETC)
The container format is irrelevant. It is the codec and the specific compression options that matter.
Nodsu is right, it is the codec that matters. The most popular codecs out there that give a nice combination of good picture quality and size are the DivX and Xvid codecs. The best quality however would be given by an H.264 codec like x264. However this would create very large files.
go to www.videohelp.com and read for about a year and then post and take the insults. Generally AVI is just a container for different codecs. Mpg is the final product on your dvd but it's generally not good for editing.
I'd say Windows avi but they take more space.
mpg is a compressed avi.
Not sure about DIVX avi version.
Actually, I prefer DivX, XviD and h.264, or even better, all combined on any movies. They mades out on excellent quality.
You can grab these codecs at anywhere.