if you are working in a DV timeline and export a quicktime movie w/ current settings, either self-contained or otherwise, and with the "recompress all frames" option unchecked, then you will get a quicktime movie of your timeline that is a direct copy of the original without any recompression
if you export with the same settings but with the "recompress all frames" option checked then you will get a copy of the timeline with a full DV recompression of all frames of the movie
if you export the same movie using "quicktime conversion" then you will get a copy of the timeline with a full DV recompression of all frames of the movie
if you want an AVI copy of a DV quicktime movie then you might want to consider using MPEG Streamclip ... there is a quicktime component included called "Save as AVI" which can be used to rewrap your DV MOV file to AVI without recompression of the original