Get a spearman, make him have good agility, and stab for the feet repeatedly until you break a tendon, and then they'll fall and you can hit them anywhere with ease.
No.
Priorities:
> Head (Eyes and throat/neck are included)
> Hands/Arms
> Feet/Legs
> Torso
> Everything else
The way the priority system works is if you have a good shot, go for it, if not, move down the list. Feet moves into priority over hands/arms when they dodge a ton.