This is another tip I've cribbed from Dave Richards, of the City of Largo.
The reason that Firefox took off where Netscape floundered is that they had the guts to just take stuff out and make it what most people need: a nice little no-fuss browser that loads fast. (Bill Joy also has a good quote about how it takes real guts to cut features -- wonder what he thinks about Java now. )
So that's what Firefox is. However, there are many features, some very useful and some perhaps more obscure, like the number of threads to keep open for downloading graphics. If you want to get at them, just type about:config in a Firefox browser window.
Right-click on an option if you want to modify it. To learn about each option, you'll need to google. Here's one page.