The Agony and the Ecstasy (1965) is a very good film that tells the story of how Michelangelo painted the Sistine Chapel's ceiling. It was based on a bestseller written by Irving Stone and it's focused ion the relations between Pope Julius II, the commissioner of the work, and Michelangelo Buonarroti, the artist. This is a good film to understand the creation of a magnificent work of art, the problems Michelangelo went through with this project, the discussions with the Pope and the criticism of some cardinals to Michelangelo's paintings. The Agony and the Ecstasy was directed by Carol Reed and the actors in the leading roles were Charlton Heston as Michelangelo and Rex Harrison as Pope Julius II.
Here you have the trailer of the film: