My problem with Creationism is this:
god was supposed to have created life and just about everything else, but who created god? If god always existed then why could life and the universe not have already existed?
That's very easy to answer! God created our minds so small that we can't imagine or comprehend how He could have been always there.
This is also in regard to Heaven. We can't imagine how wonderful and incredible Heaven really is! One day for those that believe we will be fully understanding and our minds fulfilled.