Sigourney Weaver on her unpredictable career

With more than 60 film credits (including four movies debuting this fall), Sigourney Weaver seems to have found her place, and at her own steady pace. The three-time Academy Award-nominee talks with “Sunday Morning” anchor Jane Pauley about the lesson she learned from attending Yale’s School of Drama; her launch into stardom as Ripley in the “Alien” franchise; and the secret of her Hollywood longevity.