Christians, what is your VERY BEST arguments for the existence of God?

[Tiberius]

however to avoid an infinite regress of creators, in keeping with occams razor its better to say that GOD has no cause, to keep things clean and simple.

Actually, occams razor would propose that no Gods existed, given that the universe is vastly less complex than God.

You said previously that an infinity cannot be realised ontologically, yet you are fine with the whole concept of an "eternal" God, a being who is by definition infinite. Thus, your assertion that infinities cannot be realised ontologically is either invalid (and thus there is no argument against infinite regression of cause and effect) or you must sacrifice the infinite nature of your God.