The way everything goes even hilariously worse for Clark's neighbors than for him and his family. Seriously, if you think Clark had a bad Christmas then you should check out Todd and Margo getting their asses handed to them at every opportunity.
Doubles as a Heartwarming moment. Clark's father in law, Art, has been nothing but a Jerk Ass to Clark the entire film. However, when Clark is giving Frank Shirley the "Reason You Suck" Speech, Art stands up and gives Frank a Death Glare, almost daring him to not reinstate the bonuses.
Clark's Christmas Lights, once he finally gets them working. Admit it, you all wanted your house to look like the Griswold's at Christmas.