I don't think it right to say that Capitalism killed the global economy. Without capitalism we would likely still be living as we did hundreds of years ago. Sure capitalism, or at least laise faire, can bring about major crashes which hurt us all, but to have never had it would mean we would all hurt all the time. I hate to say it, cuz I use to be more a socialist than I am now, but without capitalism, we would not have gotten very far.
To say that capitalism brought about this crash therefore it's bad is to say that cars can result in car crashes therefore we should get rid of them. Cars are also hugely beneficial, and thus the benefit far outweighs the negatives.