Reddit mentions of A Night at the Opera: An Irreverent Guide to The Plots, The Singers, The Composers, The Recordings (Modern Library (Paperback))

It's not remotely what you're looking for, but a fun introduction to Opera for noobs like me is Forman's A Night at the Opera. It's quite funny and highly educational.

EDIT: The other opera book I have is The Book of 101 Opera Librettos, which I scored for a whopping dollar at a library book sale. I'm really just bragging with that one. :D

Get some perspectives from people other than musicians. For example, my best friend is a stagehand for the SF opera and I love hearing her perspective on shows, everything from the technical ramifications of stage design to funny behind the scenes stories.

If you're trying to make opera sound cool, you'll want some segments that address beginners to opera. Like explaining the difference between the different vocal ranges with some audio clips of what happens when someone sings outside their best range. Or guides to improving your experience at your first opera.

The level of instruction in Derycke Cooke's Intro to the Ring Cycle is just right, and the wry, humorous tone of A Night at the Opera makes even the stuffiest opera interesting.

Don't forget to answer questions from your listeners too!