http://www.hiddenbyrags.com looks fine in most resolutions, however in 800x600 the header is seriously squashed. I've tried playing around with 100% tables but I can't seem to get the problem sorted. Any ideas?

At a glance, you might be able to solve the problem by adding overflow:hidden to your masthead area. This way, when the browser window is smaller than the space required, the words will just run off the right/left sides of the screen.

Alternatively you have some white space on the top right image - if you chop this off you should get it to fit (might need to adjust td widths to suit as well).

Thanks for the replies :)

You're a star the_pm, your method worked greatly.