Instructions
Turn on your Sony PlayStation3 and let the system load. Turn on the PlayStation3 controller and allow it to sync to the system.
Highlight your username and press the "X" button to load your PlayStation3 menu. Navigate to your "Settings" icon and select the "Security Settings" link which is near the bottom of the list.
Select "Change Password" and create a password for your system. Press the "X" button to verify the password change.
Select the "Internet Browser Start Control" link and turn it on. This will stop the PlayStation3 Internet browser from working. To turn the browser back on, go back to this settings page and turn the Internet Browser Start Control to off and input your password.