Mozilla Firefox is a good internet browser for everybody.
This seems rather broad a brush; I mean, truly, an internet browser cannot possibly be good for, say, the Amish. Saying "Everybody" implies "Everybody" when in fact not everybody needs or requires a internet browser. For example, Tribes living deep in the jungle.
It is fast in loading images and other pages upon surfing and browsing the internet.
I prefer to load standard pages, not other pages. Would the speed be reduced in this case? I suppose not, if I make sure to browser with images. Additionally you are saying that it's slow if you browse an intranet. Is this the case? No.
It gives a unique toolbars that helps you a lot.
Perhaps you are unaware, but the browser toolbar is pretty much standard across all the browsers (chrome being an exception, it uses the intuitive wrench to mean "menu"). Additionally, It would be interesting to know what it helps you with... aside from standard browsing activities, just like the other browsers.