After a lot of research I ended up settling on a system called Swords and Wizardry. As a set of rules it draws heavily on OD&D but includes things like an ascending AC scale rather than THACO. I pulled what I liked from Swords and Wizardry and then grabbed a few things from OD&D as well. The end result was much like what I described in my email to the party. A sort of OD&D roller-coaster with all the twists and turns of old school gaming but minus the freedom and danger.
During the game I used the television behind me to display a slideshow of old artwork from the history of D&D. My players all started D&D with 4e like I did. This game was really about taking a look back and appreciating the roots of Dungeons and Dragons.
I wonder what he meant by "minus the freedom and danger". Are the lack of those things supposed to be selling points? Of course, there was also:
I hope that as my players picked up their dice and got in their cars to drive home they had similar thoughts about the gamers that came before. People starting campaigns with characters that only had 2 hit points. Characters getting hit and losing levels. Magic items breaking and armor deteriorating. Maybe seeing for just a night what it was like back then, will give them a greater appreciation of the game they're playing now.
Or, you know, a greater appreciation for the game they played then. Either way, I hope they had a good time, and it's cool for Swords & Wizardry to get a shout-out like that.
Here's the link to read more.