you have to edit the images/footer_bg and images/welcome_panel_bg
that should do it
Wow, you're header image looks really nice.
Apart from that, in the 'css' template you will find something like this..
background : #e3e3e3 url('$settings[bburl]/images/Light/logo_bg.png') repeat-x;
delete the url('.....') repeat-x and it should all be swell.