I still use tables to design my site. I know I should use css for positioning, but when I started making the site, I didn't know CSS.

Well, here's my problem. When you go to http://www.biognost.be/food/ and check out the homepage, you will see that when you scroll, the background isn't complete. There's only background on the part that shows initially. How can I solve this? I use a div with a background to get this effect. Within the div I place the table with the content. The code for this is:
HTML Code:
<div style="margin-left: auto; margin-right: auto; width: 780px; height: 100%; border-right: solid 1px black; border-left: solid 1px black; background-image: url(../maps/back.gif);">

Can someone help me with this issue?