What format should I convert my iTunes Videos to?

Videos purchased from the iTunes Store are in a protected HD MPEG-4 format, with the video encoded at H.264 and the audio as AAC. Therefore, stripping the DRM and converting to that generic HD MPEG-4 video (with mp4 file extension) would probably be best for least loss of quality (if at all) and portability. You can always use Daniusoft again to convert to a specific format like PS3, Zune, etc.