If you want to change the background ‘wallpaper’ of Windows 8 Metro Start Screen, then try Windows 8 Start Tweaker software. This free software allows changing the background color of Windows 8 Logon Screen and Start Screen. After installing Windows 8, this is one of the first question that came to my mind i.e. if I can change its background color or picture. Now we finally have a tweak which allows changing the Windows 8 Logon Screen Color and provides the option to select a custom image for the Metro Start Screen background. See below instructions to find out how this simple tool works.
To change Metro screen color and picture launch Windows 8 Start Tweaker and select an image by clicking on the green image and select a custom picture to make it as your Metro Start Screen background. Then select a color for the metro background the same way. Click Apply and log off for the changes to be applied.
Note: If you want the image to fill out the whole screen, you should select a picture which has a height as twice as your Screen Resolution. To revert the changes click Reset from main interface.
Below is an example of how you can change you logon screen color.
Similarly, you can change the Metro Star Screen background with an image of your liking. Normally, when you change an image the background of the start screen, the middle of the background is filled with the default metro color which in the below screenshot is white. As explained earlier, you will require an image which is twice as large as your current screen resolution so that it fills the entire Metro Start Screen background with the selected image.
Hopefully in the coming days we will see more options provided by Microsoft which will allow us to customize Windows 8 further according to out liking. For now, HAPPY Tweaking!