Honestly? (As if I'd lie to you....)
I spend a lot of time introducing folks to concepts they have no clue about. Where to start?
I stage a quick play. "Hi, I've just bought a ticket to TD, now what do I do?"
You could quickly walk through what to expect:
"Show up at the sign-in desk 30 minutes early. They'll want you to log in and create an account..."
Quick, short, direct step-by-step 'what to expect' from sign-in to stepping through the first curtain. You may be able to do this in 10 minutes or less. Once you've given this broad sketch, new folks will be able to frame questions in their minds. Not ones to ask out loud; ones to listen for answers to.
Then expand on the topics you deem important - sorta just like you did.
Sorry, but if you're serious about staying within the time limit, you MUST refrain from telling personal stories, just as the audience MUST refrain from asking questions (more later).
Then, once you're near the time limit, point to volunteers (stationed in each corner, maybe), who can answer specific questions regarding specific topics:
"Okay, thanks for coming. If you have any questions about combat, see Tom (wave at us, Tom) in that corner. Fred will be out in the hall to discuss tokens, trading and equipment; I'll stay here if you want to hear more about...."
The brief opening framework will be most useful for total tyros; the mid-depth by-topic explanations will cover issues for someone who has read the forums and guides; the opportunity to 'poke at' an expert afterwards will allow in-depth 'laser-focus' answers for those who almost get it completely.
Our group found the afternoon TD 101 helpful in gelling the preconceptions we had about what to expect. Unfortunately, our schedule 'DEMANDED' that we leave immediately as the class broke up. We could have benefitted from asking questions; especially about equipping a character.
That's gotta be the toughest learning curve in the game; especially if you haven't decided on a class yet. Not sure how you can address that in an hour, other than encouraging new players to be ready for anything; go with the flow; have fun with whatever class you're dealt.
TJ