The World, The Flesh, and The Devil (1959) - 6/10
I raised my rating a bit after thinking about it some more...
Harry Belafonte plays a coal miner trapped underground during an atomic war (using some type of radioactive isotope dust that magically goes away in a few days
). Anway, he escapes and assumes that he is the last human on Earth. Arriving in New York City, he eventually meets another survivor: a white woman (Inger Stevens). She is attracted to him, but he can't overcome the racial boundaries imposed by a society that no longer exists. Then a white man (Mel Ferrer) shows up and the battle begins.
The scenes of a deserted NYC are pretty eerie. But once again, we have a disaster that, while apparently wiping out almost the entire population of the Earth, strangely results in no dead bodies anywhere.