This episode's headline: Culture of Violence; Conversation. The guests include LEONARD ERON, Psychologist; JONATHAN FREEDMAN, Psychologist; REV. CALVIN BUTTS, Baptist Minister; MARK JENNINGS, Student Journalist; JONATHAN ALTER, Media Critic; ERROL MORRIS, Film Director; CHARLES SIMIC, Poet; CORRESPONDENTS: JEFFREY KAYE; CHARLAYNE HUNTER-GAULT. Byline: In New York: ROBERT MacNeil; In Washington: JAMES LEHRER