There's a story in John's gospel where Jesus comes across a man who was born blind and he is asked whether this happened because of the man's own sin or the sin of his parents. Whilst it's true that sometimes terrible things happen to us because of our own bad choices and sometimes because of the bad choices of others, sometimes they just happen (I'm sure you know the saying).
The first great truth of Buddhism is that 'life is suffering'. However, it doesn't end there. Christians and Buddhists would join together to proclaim the importance of moving past this stage - not that we deny or even try to avoid all possible suffering, but that we accept the existence of pain and suffering in the world. Our acceptance doesn't mean that we ignore it, rather we are given the opportunity to redeem suffering by placing it in a meaningful context. If you are going to suffer, you may as well be trying to do the right thing, living a good life.
Jesus isn't drawn into the trap of blaming anyone for the man's blindness - even God. Instead he moves to heal the man. If only all our problems were so easily solved. The point is valid, however. Let's not spend our time simply bemoaning the world and our troubles, let's be a part of making it a better place for everyone.