One of Fanboy and Chum Chum's classmates is named Michael Johnson, who often moonwalks instead of walking regularly, and wears a Thriller jacket.
In "Sigmund the Sorcerer", after Sigmund performs a series of magic stunts, Oz exclaims, "Okay, my mind has been freaked!"
Another obvious one, "The Tell-Tale Toy." For a kid's cartoon, they actually pulled it off really well.
Then there are episode titles "Total Recall", "Saving Private Chum Chum", and "Lord of the Rings", the plots of which don't have much to do with the works they are referencing.
Boog, a very obvious John Travolta parody, has a sweet ride named Sandy, all three of those homages to Grease.
His voice is modeled after the Travolta character Vinnie Barbarino in the movie Welcome Back, Kotter.
Oz bursts through the door with a sword... "In the end there can be only one." (A reference to Highlander.)