The biggest problem talking about Global Warming to most people is that you get quite quickly into the science, and people's eyes glaze over in a fit of tl;dr. I'm guilty of this, myself.
"Hockey Stick" refers to the graph shown here. Pretty much everyone has seen this, because it got so much publicity in 2001.
Notice that none of this says that the planet is not warming. It doesn't say that our burning of fossil fuels isn't contributing to it. What it does say is that the science is most definitely not settled.
Act I: The Hockey Stick as viewed over increasingly long time periods (2 minutes 50 sec).
Most people have seen the famous Hockey Stick graph of sudden, rapid warming, which implied that climate has been extremely stable over history until recently. It only showed the last 1,000 years, but things look quite different if you take this back 2,000, 5,000, 50,000 years or more. In particular, look at how tiny and insignificant the hockey stick recent warming looks. Quite frankly, the recent warming looks entirely unremarkable.
The data is from the National Oceanic and Atmospheric Administration (NOAA), the U.S. Government's climate research agency.
Act II: Well, what was the big deal about the Hockey Stick? (7 minutes 30 seconds)
It was a fake. "Fake" is a very harsh term, one that is not used in this video with Ross McKitrick, a Professor who showed that the Hockey Stick was - scientifically - wrong and invalid. Pay particular attention at 3:00 where he talks about the analysis done on the Hockey Stick paper by the National Academy of Scientists whose report was "scathing" - that the results didn't support the conclusions. This is the longest of the videos, but is a great step-by-step history of the entire Hockey Stick controversy.
Act III: Hockey Stick? What Hockey Stick? (2 minutes 46 seconds)
The UN's Intergovernmental Panel on Climate Change (IPCC) issues reports every 5 years or so on the state of our scientific understanding of the climate. Their 2001 Third Assessment Report featured the Hockey Stick graph prominently. By 2007, the Hockey Stick was pretty much discredited, and so the Fourth Assessment Report simply disappeared it. Many scientists involved in the process (interviewed here) were simply horrified at how the IPCC had politicized the science.
Act IV: It's still a Hockey Stick if we hide the decline (4 minutes 59 seconds)
Despite the name changes ("Global Warming" becomes "Climate Change"), everything is still about warming. We're still told that large temperature increases will be catastrophic, with oceans rising and flooding people out. So the Climate Science community keeps looking for new hockey sticks to replace the old and busted one. Scientists from the University of East Anglia's Climate Research Unit (CRU) released a paper showing a new hockey stick in 2007. They refused to release their data, even when it was requested under a Freedom of Information Act request. In late 2009, a set of emails was leaked to the Internet where the scientists were discussing how to "hide the decline" (in temperature). This is a clear, accessible overview of what that means, presented by Dr. Richard Muller of the University of California at Berkeley, who was so outraged over this misuse of the scientific method that he has started an open, transparent climate database to be used by people who no longer trust the CRU.
Act V: Global Warming - is there anything it can't do? (9 minutes, 35 seconds)
So what does this all mean to the average person? First, it means that "skeptic" should not be a curse word; there's very good reason indeed to be skeptical. Second, it means that a scientific community that has exaggerated and fudged the data shouldn't expect uncritical acceptance of their ideas. Third, since you now have a much firmer grounding in the issue than anyone in the Press, what you read in the newspaper (Science by Press Release) goes better with a huge grain of salt. And mockery: Jon Stewart pillories the CRU crowd over "hide the decline" (no embedding allowed, so you'll have to click through). And you don't often find mockery this delicious - almost ten minutes of news reports on how Global Warming causes basically everything. Enjoy!
And so, in 18 minutes you can teach your friends and family the most important things about the whole Global Warming controversy (not counting the delicious but non-fattening 9 and a half minutes of desert at the end). At this point, they'll be better educated on the topic than 95% of everyone. Those that want to take a closer look at the science are welcome, but that's not really required.
Pass this along to those you know. Knowledge is power, for them as well as for us.