Changes the background color, which is white by default. 
Click in the rectangle on this page to invoke the Background Color window, from which you can select the new background color
Foreground color conversion: This option is designed to prevent objects from disappearing into a background of the same color (e.g. White on White) This is accomplished by inverting the display color of the object, but not the actual color setting. Color conversion will occur if this is checked. This can be controlled at the object level as well: Properties Window
Apply to all existing objects: Overrides the setting in individual objects and sets the to the 'By Drawing' default.