Note: While rendering, the status bar will display the percentage that has been rendered. Some browsers may freeze up during this process and stop updating the status bar. Don't worry about it. If your browser says that a script is causing the page to be slow, and asks if you want to abort the script, click "no" if you don't want to stop the render.
The render process may take up quite a bit of memory (at a resolution of 100, Internet Explorer 6.0 took up 30 MB at the end). If your machine is low on memory, start with a low resolution and no anti-aliasing.