From what movies are put parts in this clip? http://www.youtube.com/watch?v=UJkwDwByvH8 . I guess the color one from the '50's is a documentary, but the others?

Just from a quick glance I can tell they are mostly Public Domain stuff, probably all taken from the Prelinger Archives. http://www.archive.org/index.php

Two I recognize are the 1939 Worlds Fair, probably from the Medicus colletion, and "Boys Beware" from Director Sid Davis.