I found a code snippet today that might help here. You can add a line to your HTML file that will automatically resize the entire screen to mimick a particular resolution. If you set the width to, say 800, then the content will always appear as if you were viewing it at an 800x600 resolution--even if you are running at 1920x1200. One downside is that the quality is not top notch especially for images. But it's a quick soltuion if you are in a pinch. In a text editor, just add the following script content somewhere after the <BODY> tag of your HTML document.
Code:
<SCRIPT>
window.onload = document.body.style.zoom = screen.width / 800
</SCRIPT>
Example:
Code:
<BODY>
<SCRIPT>
window.onload = document.body.style.zoom = screen.width / 1024
</SCRIPT>
Look how big I can get!!
</BODY>
Note that where 800 and 1024 are specified, you could indicate any number you like, with lower values making everything look bigger.