Not so long ago, perhaps twenty years, perhaps a bit more, the literature of film was largely inaccessible. We were left to the tender mercies of local television statements to broadcast whatever it was they had available or that they felt would make a splash with television audiences. With the advent of videotape and now DVD, the incredible richness of the cinematic world became largely available. I can think of time during which it would have been impossible to see Rashomon or The Hidden Fortress or Throne of Blood or Ran. In fact, I would guestimate that more than 90% of film literature was inaccessible to most of us.
Now we are at Hollywood's mercy determining what will be trnasferred and thus made available. That's why it is very good to have smaller DVD companies, such as Criterion to find and rescue some of the great old films. In addition to those listed above, Criterion also made available Carl Dreyer's remarkable and moving Passion of Joan of Arc, the haunting Les Yeux sans Visage (Eyes without a Face), and The Seven Samurai among others. In this short list are the films that gave rise to Star Wars and The Magnificent Seven
And lest you think they are simply snootyville, they've also produced the "authoratative" edition of Armageddo.