Thanks - I tried some of those things, but I was rather tired and a bit frustrated when I did, which could have led to me adding the wrong files to the save.

I feel pretty foolish about my poor organization at this point.
I did put it up on the DFFD, although for the above reasons I'm not even sure it's the correct file anymore.
I never had a crash in the middle of saving, though.
Also, did you load a game, even to look at a world for an embark, and then generate a world afterwards? There used to be a major save corruption bug that occurred when data wasn't cleaned up after unloading a map before generating a new world.
I did this probably two dozen times to get a world where the dwarven civilization was dead and where the world was nice in other ways. In most cases I deleted the save before generating a new world, but not in all cases.