Day of the triffids is pretty damn good. (The book) The two-parter TV version with Eddie Izzard was aight'
All of John Wyndhams books are worth aread but Triffids is the only one i've read thats post-apocalyptic.
Never seen a film version of it, but im gonna hunt one down.
Check out The Chrysalids. Its my favorate of his, set after some sort of disasterious event with people mutating n shit.
Ah, twas the first of his books i read, at about 13. I dont remember it being set after some disastrous event though, otherwise would have mentioned it here! Only that the main characters lived on some little amish like farmstead and had crazy telepathic power and shit, before heading out to find the city.
Deffo gonna have to go for the reread!