Forgive me if I am wrong, but I am guessing that the since your video is called 94 vs 95, the THX version is the Faces?

The most obvious difference is that the pre thx has french titles, while the thx has english ones. If the ladder is a french release, how was it handled? Voiceover for the titles and crawl? Subtitles?

The THX print seems to be a little clearer (naturally) and you could see the starfield better. However, C-3P0 seems to look more gold in the pre thx version. I don't even know what color he is in the THX. My first guess (which I am sure is wrong) is "lemon".

I could be wrong, but the scene where the star destroyer tractors the Tantive IV in seems smoother in the pre thx version.

Those are my two cents. Both have flaws, but both have things the other lack that make them better.