The world is full of pain and suffering, no doubt about it. But that's because this is a fallen world, ruled by Satan. All of the suffering inflicted on the innocent--through war, disease, famine, natural disaster, etc.--is part of his plan, not God's. In God's plan, we're going to be leaving this earth someday for a better place, where there will be no more death and dying.
Why hasn't this happened yet? I don't know. I agree that there's been way too much suffering and death, and it's high time we got out of here, but God's timetable is different from mine. I suspect that it all has to play out in its own time, for God's own purposes, before the end comes. Until then, those who believe are promised a place with God in heaven, where the former things are passed away, and all is new again.