page width
Theres no hard fast rules for page widths
but for std pages that scroll as they lengthen i build sites that are 950 wide and center it, with plain color in the background that displays each side
i build a lot of non scrolling sites that the content in the divs scrolls, i usually try and keep the active part of the website to be around 950px wide x 620px high
on my screen it only uses 1/2 the screen but there is a hell of a lot of 15" monitors around that run 1024x768, so allowing for menus and even a google search bar etc it should still all fit nicely.
you can then add back ground images for the screen corners etc, that disappear behind the page content on small screens but are visible on bigger ones
