I'm sure I'm not the only Technology Professional who has heard something like this:
I click on the Start, and then the big E, and that's the Internet.
At this point in the conversation, it will be very difficult to convince Mom/Dad/Grandparent/Whoever that the Internet is anything other than what you get to with the Big E. It's not Internet Explorer. It's the Internet.
This is not an insurmountable obstacle. You just need a good metaphor.
Firefox? It's like a new TV! (Yes, exclamation point. You need to be enthusiastic. Sell it!) You get all the same channels, it's just got a different name on the front panel, and the remote is still a little different. No, no, it's still the Internet! I promise! It's still HBO when you have a new TV, right? Hey, it might even work a little better. You won't have to reset all your breakers once a week any more to make the TV come back on!