Suitably contrite after an astounding amount of admonishment, I will now turn and face full frontal the thorny problem of whether to Kill Bill or not.
These are standard counterexamples to utilitarianism, the moral philosophy that states that the morally correct action is the action that results in the most good for the most people. One reponse to these examples is called rule utilitarianism, which says that you cannot judge the morality of individual actions based on utility; rather, we should adopt the moral rules that result in the most good.
The general rule that we should kill an innocent individual to save many is a rule that, in the long run, would result in less good, and so it is not morally correct.