simple one... how to print wallet.dat to a paper 
? Simple question
The whole wallet.dat?! ? Simple question 
Say no more: [1] Close all network connections, [2] open the console, [3] use walletpassphrase "your_passphrase" 600, [4] then dumpwallet "C:/file_name.txt" command.
[5] Find that "file_name.txt" in your C directory and print it.
You might need 10 sheets of paper if your wallet.dat have used hundreds of addresses.
or you could just open that txt dumped file and write down your seed (not to be confused with mnemonic).
i don't currently have access to any bitcoin core version to test this but i had version 0.13 on my virtual box and it actually printed an extended key (xprv) in the first line.
(obviously that will only work if you are using an HD wallet not have imported keys,...)