So you have the DV file on your computer, open it in Premiere, and under Video there's only 1 codec listed?
Something's not set up right, I have like 15 different codecs to choose from... Try Virtual Dub to encode to DivX if Premiere doesn't work.
here it is. Just open your video, select Full Processing Mode and select the codec in Compression under Video and Audio, and Save As AVI to convert.