Short story in anthology. Not a movie. She develops dances that can only be performed in space.
Shara Drummond was a gifted dancer and a brilliant choreographer, but could not pursue her dream of dancing on the Earth, so she went to space, creating a new art form in three dimensions. Then the aliens arrived, and there was only one way to prove that the human race deserved not just to survive, but to reach the stars. The only hope was Shara, with her stardance.
I have the story in a Hugo Awards collection, though in fact I remembered it from Mike Ashley's book The Story of the Science-Fiction Magazines 1970 to 1980, where he says:
Hot on its heels came another novella, ‘Stardance’ (March 1977), created with his wife Jeanne Robinson, a professional dancer. She had developed the concept of a zero-gee dance and in the story this allows a disabled dancer not only to express herself but to communicate with an angelic alien race. This beautiful story ran away with all the top awards, leading to the fuller story in ‘Stardance II’ (September–November 1978) and the subsequent trilogy of books.
In 1980 Jeanne Robinson was invited by NASA to perform her zero-gee dance in space, an opportunity lost when the Challenger disaster curtailed the Civilians-in-Space programme.
On rereading the story I find I had slightly misremembered it. The dancer Shara is not disabled, though she is too tall to find a job with a dancing company. She has a male friend Charlie (Charles Armstead) who videos her dances, and Charlie is disabled after being shot in the hip by a robber. The story ends with Shara telling Charlie he can dance again in zero G:
“About you, Charlie. You’re going to dance again.”
Oxygen starvation, I thought. But she can’t be that low on air already. “Okay. Sure thing.”
“For God’s sake stop humoring me - I’m straight, I tell you. You’d have seen it yourself if you weren’t so damned stupid. Don’t you understand? There’s nothing wrong with your leg in free fall!”