Netscape is just Mozilla (except a few months behind the development curve), but with a lot of AOL commercial crap incorporated (bookmarks, desktop links, AIM, etc.) One of the great features of Mozilla is the pop-up ad blocking. That isn't available on Netscape (without a hack) because AOL (which owns NS) might lose revenue if you didn't look at the ads. Why use Netscape? Aren't you getting enough advertisements and popups in your diet? Mozilla is free, fast, stable & well mannered.
Some of you IE folks don't know what you are missing. I'm addicted to tabbed browsing (though there are some tabbed stripes of IE out there, e.g. Crazy Browser, I'm not wild about the ones I've tried- they aren't nearly as stable as Mozilla). I actually get startled by popups when I choose to use IE for some reason. The one real advantage IE has is the way it does bookmarks-Favorites. I like being able to drag them and change them on the fly without opening the sidebar or the Manage Bookmarks tool.
As to IE being more compatible, I understand that Mozilla is actually the most standards-complient browser out there. I don't have any trouble reading just about any site I use EXCEPT some of the Microsoft Knowledge Base stuff.
Opera is a great browser, too. That's my second choice (well, third maybe, after K-Meleon & Phoenix in Windows, lighter, faster stripped down versions of Gecko based Mozilla). Opera seems a little less stable than Mozy (but I like the feature that remembers which pages you had open when the browser goes tits up). Plus, the advertising banner is annoying (yes, I know I could pay for it & get rid of the banner or find a serial number on Astalavista if that were my bent, but why bother when there is Mozilla).