People dancing in movies are all doing the same dance.

Except Cher. She's doing The Monkey.

Based on that set of clips the essential movie dance is: Face forward, plant your feet apart, elbows up and out sideways, punch one fists up and then the other in a way that causes movement in the rest of your body. No real footwork is involved. The actors in the movies in that video are not Fred Astaire.