The Postwar Disney animated features produced during Walt Disney’s lifetime are often dismissed and looked upon less favorably than such films as Snow White and the Seven Dwarfs, Pinocchio, and Bambi. Peter Pan (53) certainly has its faults: underdeveloped characters, a thin story, and muddled themes that stray from those established in J. M. Barrie’s original tales. But Disney’s version is more of an allegory on a girl entering womanhood (including menstruation) than it is about a boy who refuses to grow up. And to overlook Peter Pan, and a number of other Fifties Disney features and shorts, is a colossal mistake if only for the stunning color and design schemes created by the immeasurably influential Mary Blair, which look especially terrific in this new Blu-ray release. A documentary on the adult children of Disney’s “Nine Old Men” is a surprisingly charming addition.