[El Cid]

How could 100 different cultures scattered throughout the world have the same story if the only people that survived were from just one of those cultures?

Read Genesis 9-11.

The Reader's Digest Version:

Eight people survive the Flood and land on Mt. Ararat. Noah, Mrs. Noah, Noah's 3 sons (Japeth, Shem, Ham), and their 3 wives. They have children, and they spread across the earth.

Over time, the stories they heard from their grandfathers, and great grandfathers get a bit corrupted/twisted along the way. Thus you have the same story, but with slight variations or embellishments.
God kept the original facts by using one family, the Hebrews, to be the keepers of His Oracles (God's Word) until the time of Christ. So, even though the Hebrews and non-Hebrews came from the same family (all from the ark that landed at Mt. Ararat), only the Biblical version was left intact because God protected it -- so mankind would always have a record of His message and love.

[Fuzz]

This is to be taken literally?