Phase IV is a great film. I saw it late at night on ITV sometime in the nineties. The one shot that did for me was the ants crawling out of a man's palm. I wondered at the time whether the ants themselves were being used by an alien intelligence.

Edit:

I wanted to thank you for a good write-up! I'd like to watch Death of a Shadow. And agreed about "Time Enough At Last"; there's a misanthropy in that episode that makes me queasy.