The ten commandments appear to make a lot of sense, I guess the people who wrote that stuff up probably believed it was neccesary to help people have some sort of a moral code. Though neither me nor my parents were religious perhaps without the moral code set up thousands of years ago my moral guidelines could be somewhat different. I think nowadays it is different, most people do know right from wrong and when you have a look at the few which don't they are the ones which are probably worshipping something or another.
Religion is very powerful, when the Nazis took over they made all of their churches "Reich Churches" as they were afraid that the Church may otherwise go against them and say "this is wrong", cunningly however they used the Church to brainwash people even more into the Nazi belief. However I think that if no Church was their propaganda could have suitably brainwashed a nation alone.
Religion is a useful tool of war but I do not think it is the cause, it can be used to tell people who they should be killing and why they should be killing them and instantly give them the "ok" on forgetting one of those 10 commandments. If religion wasn't there to do that i'm sure the governing power could of found another way.
Though some people argue that a lot of beauty has come out of religion (and I agree with you), such as great architecture, amazing paintings, I have to say even without religion I think people would find other beatiful things to draw and create.
Obviously this is a hypothetical situation and even if we went back to day 1 religion and worship of an idol will always come about (I think) because people need aspirations and something to achieve a goal of some sorts. I'll vote that the world would be a better place without religion, I think if there was no religion then at first there would be war and fighting such as there was anyway, and eventually people would realise what sort of things bring unhappiness to them, the deaths of others, somebody having it large with your girl,somebody stealing your mobile phone. And from this LAWS would come about which would be much like the ten commandments, I think that most people would live by and respect this laws much as many of them do today. There may still be war, people fighting over land and money, I dunno.
I think that the human race will always find something or somebody to worship.