Pretty sure I'd be one of the countless people that were vaporized in the initial blast. That's the most likely scenario.
If I survived, I'd probably be a ghoul.
If my family was in the Vault, we probably died from the crazy social experiment.
If I somehow made it all the way to leaving the Vault, my first response would be to find a nice rock and enter a fetal position, as all I can see is death, destruction, and decay.
I'd argue that most people would probably go insane if they saw all that stuff suddenly. An entire world, lost in the horrors of nuclear apocalypse. Most buildings are now just dust, same with most of those killed. The only things that remain are charred corpses, mutated humans, and half-destroyed buildings that could collapse at any moment. There is no drinkable water, there is no uncontaminated food. It basically would be Hell on Earth, a land of misery and anguish.