One can never tell certainly how every world event would have turned out without the two wars. However, without the wars maybe there wouldn't have been the regional blocs we presently have in Europe, Africa and some other parts of the world. As you will recollect, one of the reason for the formation of EU is to prevent wars among European countries. Also, many African countries will probably be under the control of the European colonial masters. Furthermore, there probably wont be the prolonged civil wars and genocides in Africa. As you know, the wars in Africa were enriched by the remnants of arms and ammunition from the world wars.
Lastly, I want to point out that the obnoxious proliferation of arms and nuclear weapons we currently experience in today's world might have been prevented without the two wars. This I say because in the wake of the end of the wars, nations were increasingly searching for ways to outsmart other nations in weaponry and sophisticated war techniques.
I hope I have been able to answer part of the question.
Good question, anyways.