Is their a simple way for a non programmer to make the c5 ad server block display as a static footer with a gray back ground that stretches the entire width?
I would try adding this to the appropriate place in your theme file. If it's a standard C5 theme, I would look in your theme folder's 'elements' folder and edit the footer.php file. This way it would display on all pages.
If this works, you should move the styling into your site's css file.