Yeah there is a huge difference in how fast the page loads....plus lets say a plug-in needs to be installed to see something (per say flash player) FireFox tells you and asks you if you want to install it, you press yes and your done...its installed automatically...
Another thing is if your computer crashes for some reason, and you were browsing the Internet FireFox asks you if you want to restore your session, so you don't lose your page you were looking at...