How do you get from "beginning of the universe" to christianity?

[Godscreated]

I've talked to a few christians recently, and they both went with "Where did it all come from?". I forgot to ask them, even if I grant that it had to be a deity, that only gets you as far as deism. Judaism, the religion that christianity is based on, was not the first religion. It didn't even have the first creation story.

Let's say we go with the popular "there had to be a beginning", and even say that Yahweh didn't need one. What now? How do we get from there picking Yahweh as the right one? Why not hinduism, possibly the oldest religion out there? Or the Babylonian religion?

People did not pick Yahweh, He has chosen them throughout history, that would be sorta like you picking your parents, you couldn't and by the way they did not pick you, they got what God gave them.
If you're going to base your assumption on Yahweh, then you have to assume that the worship of Yahweh came first, not the other religions. God being creator directed with great care through history, Christianity. It is His ultimate will.