Literal belief in the flood story

[RobbyPants]

The error in your argument/understanding lies in the above quote. Genesis 6:5 states: "And God saw that the wickedness of man was great in the earth and that every imagination of the thoughts of his heart was only evil continually." This is the reason the flood was sent, to judge mankind who's hearts were only evil continually. Your statement claims that children would not have been wicked. God states that everyone on earth was evil continually.
If you assume the account of the flood to be true, which you have to make your argument, then you must assume that everyone on earth, all the imagination of the thoughts of their hearts was only evil continually (as it is part of the account).
Today there is a door much like the door to the ark. Walking through this door, like the ark, leads to salvation, an escape from the coming judgement. This door, like the ark, is a narrow door. This door is Jesus Christ.

So I take it you don't buy into the "age of accountability" apologetics? Assuming a baby hasn't made a conscious effort to accept Jesus as his/her lord and savior, the baby goes to hell if it dies? Do you seriously think that children and babies need to be treated as adults when punishing them?

And even still, you haven't addressed the part of my OP where I asked why God couldn't have had Noah raise the children in a moral fashion. We know that children are impressionable and can be raised in a good or bad way, and it will influence how they turn out. If you are going to assert that they are wicked and nothing could be done, then I take it you do not believe in free will? Free will is the entire justification for the flood myth. You can't have it both ways. Either:

1) God could have taken steps to make sure the children were saved so they could be raised in a better way (remember, he went out of his way to magically solve all the things I listed in the OP), or

2) The children are incapable of being raised in a moral way and having it work. If that's the case, there is no free will.

There is no magical third option.