Gail,
I like your use of the phrase, "wall it off", as in compartmentalizing one's life; building a mental fortress and continuing life within it.

That's different than the concept of "Their eyes glazed over."

I personally fit into the "walled off" category. I am aware of Peak Oil. Yet I live most of my life "walled off" from it. I dare not mention it to co-workers lest they think me crazy and kick me out of my job. I generally do not bring up the topic in social circles because the ROI is usually a 99% chance of being shunned by the social group because you dared bring up an inconvenient and unpleasant topic. It's sort of like talking about a festering skin wound at the dinner table. Most people simply don't want to hear of it.

As for the very first part of your intro:

1. What is peak oil?

"Peak oil" is the term used to describe the situation when the amount of oil that can be extracted from the earth in a given year begins to decline because geological limitations are reached. Extracting oil becomes more and more difficult, so that costs escalate and the amount of oil produced begins to decline. The term peak oil is generally used to describe a decline in worldwide production, but a similar phenomenon exists for individual countries and other smaller areas.

I would suggest staying away from talking about the "amount" of oil. I know that what you say is true. Nonetheless it creates a bad frame and opens you up instantly for the "reserves" refrain. How about something like this:

1. What is peak oil?

Most people assume that our advanced economy can "supply" whatever goods are demanded in whatever quantity demanded simply because supply usually rises to meet demand.

If people want to buy the latest cellular telephone (say the Apple iPhone(TM)) then "poof" it seems like the marketplace almost overnight magically delivers the demanded quantity of cell phones at conveniently located outlets.

If folk want to acquire the latest high definition (HD) flat panel TV, then "wallah" it seems like the marketplace almost instantaneously delivers to us the quantity we demanded at almost affordable prices.

But what if the marketplace could not deliver? And what if the good involved was not a luxury toy but rather a necessity for life as we know it?

"Peak oil" is the term used to describe several complex issues all at once. First and foremost it tries to highlight the importance of crude oil to our very way of life. Second it indicates that the market cannot put a gun to Mother Earth's head and force her to year after year exgorge ever increasing quantities of a dwindling nonrenewable. In fact the physical reality is opposite to what our common sense would tell us. On a year-after-year basis, oil fields all over the world invariably fall into a pattern of giving up less and less oil and no new mega-fields have been found in the last 40 years. That spells trouble. Big serious trouble.