Considering if Fallout "happened" now, we'd all either be dead or living in holes/caves/vaults/shelters.
So.... a corpse?
However, if there is a time shift somewhere and Fallout's events happen prior to my birth, then... I'd probably be a wasteland wanderer, either dead on the side of the "road" due to treachery or not quite being fast enough on the reload. Either that or I'd try to carve out my own evil empire from the ruins, just waiting for a nemesis to appear and thus a battle ensues for the control of said empire, ending with my disappearance and apparent death, only to reappear later on with a "Fallout 3 was just a setback...".
Might as well make drama in an otherwise bleak and boring world.