+1
Will has already picked my favorite--Love With A Proper Stranger is the best film she or Steve McQueen ever made.
Natalie (and her sister) also have small but key roles in probably the best Western ever -- The Searchers. Natalie's sister plays the child for whom John Wayne and Jeffery Hunter are searching. Natalie Wood plays her as a grown woman in the last reel.
She is great with Tony Curtis, Peter Falk, and Jack Lemmon in The Great Race!!! If you haven't seen that one, then do so immediately--you'll laugh your a** off.
I think she also did an earlier comedy with Curtis--Sex and the Single Girl? Does that sound right, somebody?
Oh, and she was the object of both Frank Sinatra's and Curtis's affection in an odd but interesting war film based on a best-seller novel, Kings Go Forth. She doesn't get as much screen time as the two guys, but it's a key and emotional part. I recommend you see this one.