Tips & Tricks
If you’d like to change your lock, user tile or start screen images then go to the Start screen press Win + I, click ‘Change PC settings’ and choose the Personalize option. Browse the various tabs and you’ll be able to choose alternative images or backgrounds in a click or two.
In theory you’ll also be able to define apps that will display their status on the lock screen, although the app must specifically support this before it’ll be accessible from your Personalize settings.
Windows 8.1 extends Personalize with several useful options. In particular, it enables you to set your desktop wallpaper as the Start screen background, a great way to reduce the jarring effect when you’re bounced from one to the other.