FullBack

Screenshots

This plugin provides a very simple method for implementing a full-screen background image using the BackStretch jQuery plugin. FullBack modifies the standard WordPress Background feature in the Appearance menu. Even if your theme disables the Background menu item, FullBack checks then revives it if needed. All you have to do after installing and activating FullBack is proceed to Appearance -> Background, upload your background image and save. You can ignore the other image settings that WordPress provides as they are irrelevant when using FullBack.