Can we destroy the creationism hypothesis via the Noah story?

Creationism, at it's foundation is predicated on the bible being the "inerrant" word. All we need do is show to our fundamentalist friends that one story in that book is not literal but perhaps allegorical. If for example we can show the Noah story to be allegorical--then simple logic dictates that "adam and eve" is likely allegorical as well. First--we find it interesting that the "epic of gilgamesh" predates the biblical story by about a thousand years--and that the noah story is in large part identical to this story. Of course the fundamentalist would say this proves there was a flood--but leaves the fundamentalist in the unenviable position that their deity doesn't write original work. The fundamentalists claim that there was a water canopy and the oceans of today weren't here 6000 years ago--somethig as simple as humidty tells us that the earth would have been dead if that were the case--the avialable water (sans oceans) would have evaporated into the atmosphere-unless of course you consider humidty from the "water canopy" but if you got humidty in the air from the "water canopy"--then simple physics tells us it would not have stayed as a water canopy--but come to equilibrium. Thus in this they are left with "god held it there with his hand"--okay fine. In over 14,000 deep ocean core samples (undisturbed since the formation of the oceans) we find no gravel, detritus, etc (debris from the flood) datable to the same era across all the oceans. Okay--well agian the christian god could have made it look the way it is--erased all traces of the flood (at this juncture let us defuse the sea shellls on mountain tops caused by tetonic uplift)--okay--so this god can do anything he wants--make it look anyway he wants--is the basic position. Fine--if we look at the flood hypothesis we'd expect pregnant women, day old infants, people with no mind (mental retardation) the whole gamut of human civilization. Now--if this god can do anything--erase all traces of a global flood, hold the water canopy up, etc--then clearly it would have been simple to destroy all the bad people on earth without killing innocent animal life, day old human beings that were not "bad", retard people who didn't have the mind to be "bad". So fundamentalists--either you have a very unjust caprcious deity---who you might as well admit--doesn't have to have any particular reason to kill--it kills without justice or reason--or else we might simply figure out that the people who were to become the jews lived in the area between the babylonian and egyptian empires--heard these stories around the campfires of traders between these two empires for centuries--and incorporated some of these myths into their own religion as a tool to educate people as to what might happen to them if they cross the abrahamic god. Your position in claiming this story is literal intellectually leaves you in a virtually untenable position--it doesn't matter whether your good or bad or in between according to this story--for if your story is true your god unjust and capricious and can get ya just cause he doesn't like the way you part your hair. AGree?