And what do you want those with different screens to see? Many people will not have the same monitor you have, so don't make your display work only for yours, make it universally applicable.
There are several ways to accomplish a background image that spreads to either side of the main content, but the best for your situation, since your content is fixed width, would be to make the background images one image file with 824px of blank in the middle, and add it to the body declaration in your stylesheet:
background-image: url(../images/yourbg.gif);
background-position: top center;
background-repeat: repeat-y;
This will leave whatever background-color you have defined for body to show on either side of your images for those with larger monitors, yet not force extra horizontal scrolling on those with smaller monitors. Be aware that anyone with an 800x600 monitor will be forced to scroll horizontally to see every page of your site. If you don't mind annoying them, you can leave the content at 824px; otherwise, you would be well advised to make it something like 750px.
By "static", do you mean that it should stay in position on the screen when the user scrolls up & down? For that, you can use
background-attachment: fixed;
except that IE6 doesn't recognize that property value and will ignore it, letting the bg scroll with the content.
