The experiences of the Bielskis is informative. But the movie "Defiance" is, ummh, not so. I think I have recommended before (probably in this thread) the documentary video "Partisians of Vilna." "Vilna" now called Vilnius, the capital of the now independent Lithuania, was a major center of Jewish culture and a large part of the city was Jewish before WW2. The Germans captured the city, and created a ghetto. Some chose to run to the forest to survive; some stayed in the Ghetto. People living in a "civilized" city suddenly are faced with stark survival choices.

The documentary traces what happened to both groups, those who stayed and those who ran and fought; the problems they faced and conflicts they had.

IMO, it is about as close an analogy to how we live today as I can find (the Bielskies were a very rural based group), and the choices we might have to make, and problems we might face if all goes wrong.

Hard to find, but I highly recommend it.