When Arthur catches Doug watching one of the movies he starred in, it's a clip from the film The Taking of Pelham One Two Three (1974), in which Jerry Stiller plays a police officer.
In the scene where Danny and Spence start to share a bedroom, there is a "Warriors of Grün" movie poster. On that poster you can see the word Yuspa top row in the middle
Yuspa is the last name of a producer, Cathy Yuspa, of the show and a running joke.
This episode was dedicated to the memory of Kevin James and his brother Gary Valentine's father, Joseph Valentine Knipfing.