RICHARD PRELINGER is a archivist of films you probably thought were not worth saving: educational, industrial, and public-service films made from the 1930s through the 1960s. He's the director of Prelinger Associates, Inc., and he's collected some 25,000 films with titles like "A is For Atom," "Good Wrinkles: The Story of a Remarkable Fruit," and "Are You Popular?" PRELINGER became interested in the historical importance of such films while researching, and obtaining the rights for footage used in the films "Heavy Petting," (not yet released) and "The Atomic Cafe." PRELINGER has compiled and edited a two volume videotape and disk documentary, "To New Horizons: Ephemeral Films 1931-1945," and "You Can't Get There From Here: Ephemeral Films 1946-1960." (the address for Prelinger Associates, Inc., is 430 West 14th St., Room 403, New York, N.Y. 10014 (212) 255-8866.)Also, in this half hour, TERRY talks with writer KEN SMITH who is writing a book on the films. SMITH is co-author of "Roadside America" books (volumes 1 and 2) about tourist attractions in the U.S. He's also an archivist with Prelinger Associates.