This tutorial is useful if you want to ethereum wallet backup and you can do that easily by following the steps below:
Step1: Select "Files -> Backup -> Accounts" in Ethereum Wallet.
Step 2: Go to "Keystore" and open it.
Step3: You should see something similar to the screenshot below inside Keystore. Copy all of your Ethereum wallet addresses and put them in a different folder if you have more than one.