Cross-Browser Compatibility of Existing Website

I have an existing website. [login to view URL] - The website looks fine in Chrome and Firefox on my Mac, however, when opened in Internet Explorer 6, 7, 8 the website doesn't load properly. It appears that a few of the CSS rules are not cross-browser. There are a few ways to make the website cross-browser, such as creating rounded corner image files and adding some rules per area to make it load right. This project covers making those changes and others necessary to make the website look similar cross-browser.