I use 800x600 and most all pages look and resize good except the home page. It is usually the center story block that makes the page too wide. In almost all of the themes I have gotten from here I had to change the css class .content in the story block footer in the story_page.html to one I added and change the font to arial instead of verdana so that it wouldn't push the page off the screen. A couple I have had to add line height to and draw them down because the TD cell was taller than the bg image. Also, in the footer of the story block, only 2 to 5px.