stupid question about page format

[goresnet]

On my computer at work, the home page is center-justified with some empty blue on either side of all the text. On my home pc, it seems like it fills the screen, from left to right, no empty blue sides. On both monitors the resolution is 1280x1024. Zoom at 100% and text size medium. Work pc IE6, home pc IE9 beta. My home pc used to fit like my work pc, even when I had IE8. However, the change started before the switch to IE9, so I don't believe that's a factor. My 21 month old son loves pushing buttons on the keyboard, and I'm wondering if there is something he could have inadvertantly changed, that I'm not aware of. Any ideas?