First off, I dont usually like to get into debates about religion, only generates conflicts, but wucas, you seemed to have a few questions, so I will answer them.
The big bang theory is more a theory, as it says it, not a fact. But it's the closest we've got from our current proofs. Religion comes from nowhere. Peoples just "thought it up", to explain phenomenons that they could not yet understand. There is no proof that god ever existed. It is not for us to find god doesn't exist, but for religion to find proofs god exist. I could say "I am god, prove me wrong" and I would stand on the same point as religion, while having as solid arguments. There is a multitude of religions also, making it even less likely that one would be true.
Because science base itselfs on facts, observation and the such. Religion comes from faith and beleif, it has no rationnal origin (for example: a dragon vs a rock).
Religion is an old concept that was created to explain phenomenons which we could not yet understand. For example, ghosts have been imagined after seeing gas coming out of the cemetery grounds. Making whitish looking shapes. But we now know that it is a chemical reaction with the decomposition of the body. Same kind of pattern for the religion. So, as it goes, religion is more "medieval" if you prefer.
Now from a stand alone point. This is a funny little thing to think about. There is a galaxy located 13 billion light-years away from earth. From the light-years definition, it means it took light 13 billion years to reach us. Therefore we couldn't see it before 13 billion years after it sent it's first light towards us. If the universe was created in 7 days, how do you suppose the light ever got to the earth? (especially considering our universe is a few thousands years old "apparently")
Where are the dinosaurs in the religion?
Also, funny mental puzzle: If god can do anything, can he make a rock that he cannot lift? Oh... paradox. Now, let's take this question into reality, could he really do it if he existed? Think about it.
This is the kind of question you get when religion intertwines with reality, because it does not originate from it. It comes from the mind. You never saw a bird pray at an altar either.
I'll leave it at that, religion is a good belief, if it makes you feel better or more confident in your life, using it might help you, so choose whichever you want.
-Jawarisin
PS: Just for you wucas