There are still a lot of people who use Microsoft Internet Explorer. If you are trying to convince them to give Mozilla Firefox a try, then it might be a good idea to point them to www.switch2firefox.com . Everything they need to know is conveniently gathered in one place. There are both theory, in terms of happy customer reviews and lists of reasons to switch, and practice in the way of direct links for downloading Firefox and all the vital plugins, such as Macromedia Flash and Shockwave, Java, etc.
This site covers Microsoft Windows, Mac OS X, Linux, and Solaris.