It's difficult to give an honest answer if you (I mean everyone, including myself) are not in a position you have to take such a profound decision. I mean, you never know how you will really react. You hope you will be a hero who takes the right decision, but maybe, in the actual moment, you will be a coward. Listen to your conscience and act accordingly, that's what I try to do.
This is also an interesting area from the other side I think. Some people believe that they can act out some terrible behaviour but come down to it, can they? I think given the right circumstances we are all capable of the worst humanity can deliver and the best.