Looks pretty comprehensive there, Frank. If you want some more maybe I'd throw in the 2 chorder "Jambalaya" (in a nice 2-step Cajun rhythm), Blue Moon of Kentucky, maybe "Guantanamera", "Show Me the Way To Go Home" (could introduce 2 more chords to them later in this one, the II-7th and the VI-m), 3 chord versions of "Jingle Bells" and "Rudolph" for the season. Like Bobert said, lots to choose from.

As far as people's familiarity with the songs goes, I don't think I know any more. I've launched into "Four Strong Winds" at sing-a-longs only to be met with blank looks. I thought everybody knew it around my neck-of-the-woods. They did when I was young, either from Ian & Sylvia or else Neil Young. And a couple of years ago I had a 13 year-old kid I was teaching mandolin lessons too. Was showing him as a primer "Doggie In the Window" because I figured he'd know how it should go. He looked at me and said he'd never heard the song before. I couldn't believe it. Figured EVERYBODY sang that as a kid. WE did, along with "Don't Fence Me In" and "Swing On a Star" and "High Hopes" Even though I grew up with Folk, Bluegrass, Country and Celtic. There were certain songs just everybody knew. Now it's just the Christmas Carols.

By the way, how does "I Ride an Old Pain" go? ;)