It pretty much depends on the nature of this god. If the god isn't much concerned about humanity, or allows people to be who they are, then all that would happen in my case is that I recognize that a god exists, but since very little in my life depends on the existence or non-existence of a god, not much else would change.
If this god, however, demanded obedience and punished disobedience then I suppose that I would be forced to obey -- especially if the god had the power to exact punishment. How obedient I would actually be would depend on how severe the punishment would be for disobedience and how aware this god was of my actions.
Now if the Christian fundamentalists are correct, and this god actually demands my
love and
trust, then I would be in trouble -- love and trust are things that are earned, not given, and if this god didn't behave in a manner I found worthy of love and trust, then I would be unable to love or trust it, and so would end up damned for eternity.
"Religion is the best business to be in. It's the only one where the customers blame themselves for product failure."
-- Ellis Weiner (quoted on the NAiG message board)