Wow, this is really hard for me to read.
I hardly ever think twice about killing a rat or a mouse to feed my animals, but if it ever came down to killing one of my snakes I don't think I would be able to do it. That being said, I think (as hard as it is to even imagine doing something like this.. it makes my toes curl just thinking about it) crushing the head would probably be the fastest. As long as there's someone else to do it. I'd probably miss and make things worse anyways, my eyes would be too teary.