From a I'm so glad it's released point of view, Volume 8 of The Stooges and The Keaton Educationals. I'm also glad the Chaplin Keystones have what appear to be a valid release instead of cheapo public domain.
As far as good movies, MODERN TIMES, SHERLOCK, JR./THREE AGES, and STEAMBOAT BILL, JR. win. The former is just another re-release on DVD and the latter is a debut in a new format.