Well, how about

Beautiful Maria (either Bolero or Rumba) from Mambo Kings?

There are a couple of good mambos on that CD, too, just can't remember the names.

One of my favorite waltzes is "Lara's Theme" from Dr. Zhivago, but there's no soundtrack from the movie (I don't think so, anyway). There are probably a lot of versions of it, though.

Jive - What about "Yesterday's Hero" from Strictly Ballroom?

There are all kinds of good hustles from Saturday Night Fever.

There was a soundtrack ablum for Dr. Zhivago. However you can find Lara's theme on some dance CD. It's actually a viennese waltz, not a slow waltz (the melody is slow, but you are actually dancing to a more subtle underlying rhythm at viennese tempo)

For your slow waltz there's always Moon River, or "a time for love" from Romeo and Juliet. Actually a lot of recent movies have themes or major numbers that have been wonderfully re-recorded as slow waltzes by dance orchestras (the soundtrack versions are often a little outside comfortable tempo): Dances with Wolves, Cider House Rules, Shrek, Pearl Harbour, the Patriot, Moulan Rouge, Gladiator, and many more.