That duck must have been packing quite a bit of TNT, since Superman flew off and the fire from the explosion could still be seen through the back door of Lois and Clark's home.
Lois mentions that The Sound of Music is her favorite movie and that she was the most popular babysitter at her high school. Of course, this was all while The Toyman had a gun on her, and she was explaining why she qualified as a mother figure for the children!
In this episode, Martha and Jonathan are celebrating their 35th anniversary. Lois says that she and Clark are just thirty-four and a half years behind them. So, Lois and Clark have been married for about 6 months.
We finally see Perry's wife Alice in this episode.
This version of the Toyman has a female assistant named Wendy, rejects "growing up" and associates it with both dying and adult deceit, collects children he considers lost or neglected, and in arguing with his prisoner Dr. Klein what to do with the inadvertently teleported Lois is told "All of your children need a mother!" All these refer to the character of Peter Pan, the magical boy who refuses to ever grow up, created in several works by James Barrie, most famously his 1904 stage play.
When reading the reply to his personal ad, the respondant says among other things that she likes pina coladas, a nod to the infamous song "Escape", also known as "The Pina Colada Song", in which a man's personal ad is answered by a former unappreciated lover.
Dr. Klein: (as The Toyman comes in) Ladies and Gentlemen, Dr. Demento is in the house!
Dr. Demento is the nom de guerre of Barret Hansen, a radio disc jockey specializing in novelty songs and pop music parodies. He's best known for bringing the music of Weird Al Yankovic to the attention of the general public.
Toy Story is the name of a popular animated movie which came out shortly before this episode.