I would like to ask webmasters, what optimal website page sizes are?

Most people are using widescreen displays with a minimum width of 1280 and a minimum height of 800 so I would say somewhere around 900~1100 for width and 500~600 for height as your primary area.

Others may have some feedback on this, and of course there will be individuals who run larger (and smaller) resolutions. You cannot make the site appear perfect for everybody without a *LOT* of work but you can make it look good for a great majority.

Mostly people are using 800 X 600.
I'm too.

800x600 is pretty close to the range I stated (900x600) or so

There are ways to make the page optimal no matter what size screen/resolution is being used. I'm not positive but I believe it can be done using CSS - anyone here with more knowledge than I?

I design with a minimum width of 800 pixels. Even though my screen width is 1024 pixels.

There are many grid based css frameworks that are using 960px wide. One that comes to mind is 960.gs project.

I think to reach the widest majority of users 800 x 600 is pretty safe.

We (6sync) decided to buck the trend and target 1280px screen width! This was based on the thinking that, in general, our target market are tech-savvy and we believe more likely to be using either 17"+ desktop LCDs or 13"+ laptops. We also dropped support for IE6 (too hard basket [we have limited resources]).

Whether this was a good idea or not.... I can't say

K, now make everyone else do the same and my job will be much easier

I seriously don't understand why so many people are still using IE6.. Can anyone else explain it?

I can’t offer a real reason but many of the places that are still on ie6 seem to me to be colleges, schools and some offices the only reason I could gather for it is the technicians are yet unsure how ie7 or even 8 will affect their security and will work with the various filtering software they use.

At least that is the blurb that tends to come from them, cant really see much cause for concern although I haven’t yet seen a full office on vista... (rightly so .. in most cases) so I’m doubtful it we will be shot of it for a while

Mostly people are using 1280 X 1024

Looks like I still have some 20% of visitors using 1024 width resolutions, so it wouldn't make much sense to upset them.

As for IE6, lots of Windows users stick to what they have as they don't know any better. It'll take a while for them all to change computers and OS.

MOST of the corporate world is still using IE6. Large organizations that I have dealt with in the past are still very much behind the times when it comes to new technology. One major firm that I worked for is still using Windows XP as the primary operating system. Granted they are rolling out Vista, but it's a very slow process in large organizations - especially when some custom programming will not work on the Vista Platform.

As for using a variable size on pages, when I used to design years ago I did this. It's commonly referred to as a Liquid page, or Fluid Design. We had multiple splash pages at various sizes in order to capture the necessary market.

I think operating in a liquid design these days is a suicide mission given that people have 24" monitors and others still on 15". If you are concerned about how the page looks, and you want it to look the same for everyone, you specify the width of a page. Not doing this can leave a page looking very "empty" as the text stretches accross the screen.

Then again, on a 24'' screen, empty space is not much of a surprise. The user gets used to it.

Without a real reasoning behind it, I find that I am switching to fixed width designs, although I was very much a fan of fluids.