The size of the user's web browser window is probably one of the biggest headaches when it comes to web page design.
The trouble is not everyone has the same size monitor running at the same resolution. To make things worse different browsers have different viewable screen areas.
It is much easier viewing a web page that is designed for a smaller screen than one that is designed for a larger screen where you may have to do allot of scrolling left and right to read what is on the page.
Thankfully, the minimum resolution most people use these days is 800 x 600 pixels and either use Internet Explorer or Netscape web browsers. In this case the minimum live space you can work with is 783 x 398 pixels.
By designing the web page for a live space of 783 x 398 pixels you a guaranteed that the web page is going too easily viewed by the majority of web users.
In fact this website is designed for this amount of live space, but when the page is viewed on a higher resolution monitor with more live space the page automatically resizes to fit the browser window.
The resize feature of web browsers is something that works for this site, but you may find that it completely ruins your much worked on page design. However, this can be overcome by using a fixed width page design where the page width is set in pixel size the page will then have the same layout whatever screen resolution the user is using.
The length of your web pages is also important. It is best to try to keep pages under 3 page lengths long and if necessary split the page into 2 or more pages.