By Bruce Forer
Updated June 21, 1996 at 04:00 AM EDT

The American dream has taken more hits than Rocky Balboa, and the latest ”left” hook comes from media archaeologist Rick Prelinger. These four discs containing 25 arcane and campy industrial, educational, and advertising films from the 1930s to 1960s illustrate what Prelinger calls the ”darker side” of capitalism. (Eight more discs are scheduled.) Our Secret Century, Vols. 1-4 is sure to delight any graduate student in sociology looking for a thesis topic; for the rest of us, this slickly produced and easy-to-navigate jaunt is surprisingly entertaining. One 1957 promo, for example, lovingly follows a glamorous housewife dancing her way through a gallery of gleaming Frigidaires while a deep-voiced narrator hypes our brilliant future as consumers. The dual message throughout: Conform and buy. A-