I pretty much never get a crash that I don't deserve because of other things (the other day it was leaving Audicity recording some audio in the background and filling up the disc without realising, stopping several other programs from doing their own/the OS's memory-to-disc stuff) and I happily run DF on a nice low-powered machine without much in the way resources and long enforced waiting for load-up/save-out/seasonal-turnover is part of my "get out of the seat" strategy (after making notes about what I was just about to do when the season save kicked in) as well as a handy fallback.
Not only FPS, but also pause-play for micromanagement could be stopping a seasonal save from kicking in in time to lose only a little work. It's still only one season (perhaps one migrant wave, maybe one trading operation, and other incomers both friendly and unfriendly) but mass-designating the digging around the caverns, setting up a complex burrow to encourage a new industrial area to be dug out first, all the little micromanagements that made your season take an hour or two in real time, though they go much quicker a second time, sometimes you want to recover from the RSI from tap-tap-cursoring, etc
But finding the setting to enable that and then resolving why you-broke-DF/DF-broke-itself is something I should say that you OP should resolve first. The hidden depths make it susceptible to edge-conditions in logic, and some may still need whittling away.