The Man from Earth
Horrible sound quality, fair-to-bad acting and/or directing, and a mediocre screenplay spoil a compelling story. It felt like a more serious twist on Mel Brooks' and Carl Reiner's 1000-year-old man gag. I'm not sure I'd recommend it to anyone, unless that person liked to talk bullshit and was very open-minded about religion. I'm somewhat shocked it's so highly-rated. To speculate on why would probably be to spoil it for whoever dares to watch it.
Silent Running
I thought for sure I'd seen it before--maybe I fell asleep on it or something. I had to watch it because it was high on a "best" list, and I'd seen just about everything else except the (?!) Japanese titles.
If you can stand the repeated offenses of Joan Baez singing tree-hugging music, there's a fairly trite ecology message there, which can be said without clubbing you over the head. The visual effects and cinimatography, of course (if you follow science fiction, you already know) are incredible for 1972. The sound was 2-channel (mono), but tolerable. Some of the technical aspects of the story were laughable. Worth seeing for technical aspects, if not to see Bruce Dern as a young psychotic rather than an old son-of-a-bitch.
addendum
Turns out it was 1972 and the sound was "2-channel mono." I don't even know what that is.