Most of these can be downloaded at archive.org.

Phantom of the Opera (1925, directed by Rupert Julian) [IMDB]

The Cabinet of Dr. Caligari (1920, directed by Robert Wiene) [[IMDB]

Nosferatu (1922, directed by F.W. Murnau) [IMDB]

Frankenstein (1910, directed by J. Searle Dawley) [IMDB]