William Malcolm Goodhart, screenwriter and creator of the 1960s hit Broadway comedy “Generation,” died of heart disease Oct. 20 at his home on Shelter Island, N.Y. He was 74.“Generation,” Goodhart’s first play, opened in 1965, was directed by Gene Saks and starred Henry Fonda as a parent coping with an unconventional daughter and her husband. Although it received lukewarm reviews, “Generation” enjoyed a long run nonetheless, and in 1969 Goodhart adapted it for the bigscreen, starring David Janssen and Kim Darby. He later became a writer and producer for Warner Bros. Screen credits include “Exorcist II: The Heretic” (1977) and “Cloud Dancer” (1980). Goodhart was a physics major at Yale U. before enlisting in the Army during World War II. After the war, he returned to Yale to study drama.