You know what? Keeping posting in threads like this is always "food for thought", and I learn (or correct) techniques, methods or scripts every time - not counting the constructive comments, everytime well accepted. Thanks to all the forum members!

You_Too, thanks for your help - AntcuFaalb, thanks for your script.

Now it seems to work, and the results are the same of the image You_Too posted. But, as I have the DVD, I could test every scene I'd like to... so, what about these?

While the first result is bad, the second is awful and unusable... What do you all think I should do for these scenes? It will be better to use the BD, the upscaled DVD (I've done it for the second scene, check out the last test clip some posts before - or (the best option to me) - to see if the DVD chroma lies perfectly (or almost) onto the BD luma?