OK, I lived through Hurricane Katrina, and she took everything I ever owned so I've thought about this alot....
I have a stuffed bear that was given to me the day I was born...It is held together by my tears through out my almost 40 yrs. (It made it through Katrina only because it was at my Dad's and floated ontop of my matress, not a wet spot....but he only had 5ft of water)
I'd grab my box of insurance and important papers.
And I'd grab my computer, most of my pics are in it as well.