Thanks for the help guys!
Indeed, from me too.
So I can literally just move the wallet.dat file to usb, put the usb in my fireproof box, burn down my house, open the fireproof box, take my usb stick, put it in a new computer, download the client, put the wallet.dat file on my usb in the place of my new clients' wallet.dat file, and have all my coins??
Also, do you have to "Backup" the wallet after each transaction you make, i.e., are the transactions themselves -- and the latest balance -- also stored in the wallet?