While I have yet to see the film with the Philip Glass score, I do agree with Prospero, that the original score is unremarkable. It's not that it's bad, it just doesn't move you the way a more powerful score should. That being said, it is still one of my favorite all time films.
I love the lyrical, true fairy tale feel that Cocteau creates. I remember seeing it on TV when I was quite young, and being mesmerized by the moving arms holding the candles, and pouring the fathers wine. I also love the way the mantlepiece faces release smoke from their noses, and Belles mystical glide down the hallway. It is tribute to Marais performance of the Beast that you wish he never turned back into the prince. I realize that's what Cocteau intended, yet I didn't feel as strongly about the Disney beast turning back, though Disney obviously knew a good thing when they saw it since they so liberally borrowed from it for the animated version.