I tend to take a variety of TV show DVDs whenever I go up to Iowa, both to have options on the plane ride and to try introducing my parents to TV shows I’m watching.
I didn’t have time to show them anything when I went up for birthdays in August, but Mom saw Nathan Fillion on the cover of Firefly Disc 1 and mentioned that she liked him in Castle, so when I went up for the funeral, I took Disc 1 again, and Mom ended up being disappointed that I only had 1 disc with me.
When I went up for Christmas, I took the rest of the series and Serenity, and Mom got through the series in 2 days. We did some traveling, so she didn’t see Serenity until a few days later (though we did have a long conversation about the characters on the drive).
Her favorite episode was The Message.
Also, in Serenity when The Operative showed up at the transmitter, Mom thought everyone was going to die, but Mal would get the message out first.