Small Company Builds Website. IE GOOD. N

My company had to build a simple static HTML website, we used to have a bigger badder website that is about to go away. It will be replaced soon, it is www.breathnet.com.
The new simple static one has alot of graphic images. It uses style sheets, it is http://66.149.37.251. It runs on an Apache web server. We are in QA and notice that IE works great but Netscape works not great. It takes Netscape 20-30 seconds to load the homepage. Navigating between pages with Netscape takes often 20-30 seconds. I was wondering if any tags or other stuff we have in the HTML can be changed so that Netscape can work good, like IE.