I just happen to have a spaceship here in my possession that you might find useful, but better come get it quick before I decide to go with the suggested option #3.
Contrary to what has been suggested, I do value human life, in fact all life, above all things, it is the reason I do what I do in life. My hypothetical button is the quick and easy way to starting over, passing the buck onto some other civilization that will more than like form somewhere, because any developing species will most likely go through what we're going through. Yes, life feeds on death, which would be fine if it stopped at death. In fact I'm quite comfortable with the concept of death. I don't want to stop people from dying, I want to stop people from suffering.
I don't mean to sound terrible... but if things are that bad for you, and you feel that humanity is a lost cause... um... why are you still here?
Aha, but here's the trick, I don't think humanity is a lost cause, in fact I firmly believe that we will all eventually rise above the need for conflict and war. I realise however that the road to that point is loong, and not easily traveled. Pushing a button to end the world would be a purely selfish act, and if I were given the opportunity, I would push it, since I am human, and humans are selfish beings. Kinda like when a child steals a cookie from the cookie jar, even though he knows he'll more than likely be given a cookie later, and he knows stealing is wrong... but he knows he won't be caught, so, why not?
* Eliseth hands Prolix the keys to the spaceship. "You go ahead, I'll stick with option #2"