The fullscreen version usually shows more animation, and I'm fascinated with fullscreen versions in general, whether open matte or pan & scan. I even started a thread on this:
http://originaltrilogy.com/forum/topic.cfm/Fullscreen-Laserdisc-DVD-Preservation/topic/15846/
As for the original Brazilian dubbing of "Snow White", Disney supposedly keeps copies of the foreign versions of its movies, so they might have it. However, I don't think they'd bother to check or make even a small clip available ( just for the record, the 1966 dubbing is a gem in its own right ).
By the way, I heard the original Spanish dubbing is gone, too.
Even if they censor and over-restore their films, Disney's record regarding preservation is still much better than what we see happening with other studios.
On the other hand, they did not preserve Fantasia's original narration, so who knows what they still have, and what has simply rotten away?