Ah, well that veers rather close to GD territory. “Great Debates” == “More emphatic than usual IMHO’s”…IMHO. 
The First Noble Truth is, life is suffering. Life is troubles. No way around that–it’s built into the very fabric of living and being human. Once cancer and AIDS join the troubles-of-the-past file, along with things like dying from appendicitis (yes I’m aware people still do here and there) and smallpox (at least until someone uses some funk military-grade variant on it), other troubles will replace them, some of which we can’t imagine yet. When those troubles are solved–and they will be, because that’s what people are, problem-solvers–other ones will follow. That’s life, and there aren’t shortcuts.
But hypotheticals, yes. Let’s look at possibility one: you’re being offered this “receive benefit A for the anonymous sacrifice of X” from someone/something else. Said Something has the power to do A–but won’t unless you personally will the death of another human being? That Something is…well, a jerk. Life’s short and precious, I don’t willingly truck with jerks.
Possibility two: this hypothetical rests in some hitherto-unexplored bit of natural law, you’ve just happened to discover it. That’s more squarely in a philosophical/ethical debate. My answer’s still no. I’d be lying if I said it wouldn’t be enormously tempting to say yes, but ethical behavior isn’t necessarily the easy way.
The motto of the “World Game”, from (popularized by?) R. Buckminster Fuller is “To make the world work for 100% of humanity, without ecological offense, through spontaneous co-operation, to the disadvantage of none.” Italics mine, here. It is, obviously, an ideal approach to dealing with the problems facing the world, emphasizing non-coercion and a defiance of the “truism” that life is a zero-sum game–both also GD-able, of course, but I know my position.
Now tying these bits together–there will always be troubles and problems to solve. And though the process is slow and painful, and leaves suffering in its wake, those problems do get solved once sufficient numbers of people simply gain the will to do so.
If the world actually worked by the ability to wave one’s hand, cause some stranger who’s never done you any harm to drop dead (or die slowly, screaming and twisted in agony, as loved ones looked on helplessly–how the hell would you know? And why care, you’ve got your million bucks out of the deal, or get to be the Cancer Slaying Hero, whatever strokes your ego in the right manner)–if the world worked like that, it’d be a worse place. Because you might wish for an end to war. The next person using the option might wish for an end to the filthy darkies. The next person, an end to the white devils, or the “Jewish Bankers”, or for something terrible to happen to the Joneses new boat that’s so much better than his. Then someone from VHEMT–without valuing that “Voluntary” bit so much, might thoughtfully rid the poor Earth from the scourge of human reproduction.
Hmm. There’s a story in that.
Anyway, the answer’s still no. Others will and have say “oh heck yeah! Pass the button!”, and that’s their right.
Just be glad there is no button.
