The end is nigh! We have been obsessed with how it all end for a long time, and movies give us various ways that it could happen and how we would all act at the end of things. The list below is only roughly spelled descending from overly epic to contemplative--not a judgment of rank. Feel free to include any I have forgotten...except zombie and alien movies.
For the sake of clarity, let's leave them off the list. I know that precludes great films like "Invasion of the Body Snatchers", "Omega Man" and "Dawn of the Dead". But this list would have to go to 500 to get all those in. This list will be limited to titles in which the world itself is coming to an end by natural, cosmic means (sorry, "Hitchhiker's Guide to the Galaxy"). We'll allow nuclear war scenarios, though.