Major differences in this version compared to others are Anamorphic video, ac3 sound, improved video bitrate, and an extremely high amount of care taken to ensure that the result is as good as possible given the source (an old film print on analog medium).
Definitive Original Edition (NOT Special Editions)
Video: ~4500kbps 3-pass CCE encoded
anamorphic 23.97 fps
Audio: 192kbps Dolby Surround ac3
Source is the 9-disc LaserDisc set, the best available source for these versions of the movies. Encoded through S-Video, with great care to get 0 dropped frames, correctly merge the 6 disc-sides per film, properly convert the framerate, deinterlace the video, clean up analog noise w/o blurring the image, normalize the sound, and fix the various field-order errors in the original source. Basically, it's unlikely you'll see a better version of these films any time soon.