I should have added 1600 x 1200, never realised it was so popular.
In terms of fixed width and full width websites, what I mean is that T2W is fixed width in the sense that what ever the size of your browser window the width of the content of the website is fixed at about 750 pixels. So if you viewed the site on a gigantic 21 inch monitor at 1600x1200 the width of the content would remain the same, but you'd of course be able to see more vertically, but the site I'm sure would appear very small in comparison with the size of the monitor.
You're right bonsai, although we are at a fixed width, when someone posts a particularly large image the only thing that can happen is it stretched the fixed width to accomodate the image. In web design, you simply can't crop an image or resize on the fly, without some real effort - and you're probably wouldn't want to.
An interesting point is that in terms of reading legibility a word lengeth of about 12 words per line, is about optimal. Any more and you lose which line you're reading, and less and you eyes are constantly dancing across the page.
But with a full width screen you can also increase the font size which would make the writing more readable on a larger monitor - I dread to think of those members who have to squint to read the writing on their huge monitors.
To get an idea of full width websites here are a few financial ones that really are full width:
www.fool.co.uk
www.elitetrader.com
uk.finance.yahoo.com
Here are ones that may appear full screen (since the header is fullscreen) but if you look at the actual content (the body of the website), they're also fixed width:
www.advfn.com
And these are fixed-widths (although some may be centred or aligned to the left):
www.trade2win.co.uk
www.moneyam.com
www.ft.com