I believe in God in the strictest sense of the word that implies "God=creator". Something must have created this universe. Some would say Big Bang, others would say the collision of two universes, others would say the Christian God in six days, others Allah, Jehovah, etc. Whatever the name you gave this entity or event doesn't matter. This universe was created by something because something can't be created out of nothing. Since this universe is immensely complicated, you can assume the creator is atleast equally complicated.
Some might ask then who created this creator that created the universe. I am not capable to answer this question, nor is this question important to me, because the only thing I am interested on is on whether or not something created this universe.
That is as far as my flimsy certainity extends - a creator, which most probably is/was complicated more than I am now, created this universe and I choose to call this creator God. That doesn't mean though that I believe this God has a personality or is currently all-powerful to alter its creation.