The Godfather covers all of part I, and the flashback bits of part 2, as far as I can remember. Looking at it now, all I can remember about the entire story, book and movies, are Al Pacino's eyes. :)

Oh, and Anne is a must! (although you ought to be warned, she can get a trifle arch, and a little too clever sometimes.) But the blessedly Victorian is very nice, sometimes.