I should use System Restore to roll back to a point before you made the change.
You don't need a registry edit to change your wallpaper. Just go to Control>Panel>Display>Desktop tab. Click the browse button and pick an image from your hard drive.
OnePlus 5 review
See the work of famous artists playing with toys
iPad Pro 10.5in (2017) review
Comment faire une capture d’écran sur un Mac ?