A typical episode of Toonsylvania starts with a cartoon featuring the adventures of Dr. Vic Frankenstein, his assistant Igor who always sets out to prove that he's the real genius instead of Dr. Vic, and their dim-witted Frankenstein monster known as Phil. Before the second cartoon, there is an animated vignette where Igor is on the couch with Phil and tries to fix the TV remote, but every episode, there's a new problem with it (a running gag akin to the couch gags seen on The Simpsons).
After that, there is a cartoon series called "Night of the Living Fred," about a family of zombies (sometimes, a parody of a B-horror movie would air instead of a "Night of the Living Fred" cartoon). This segment was created by Mike Peters, a Pulitzer Prize winning cartoonist.
After that is a short segment called "Igor's Science Minute," where Igor gives a science lesson (be it a musical piece or a spoken piece) that always ends in disaster. The final segment is "Melissa Screetch's Morbid Morals," where Phil the Frankenstein monster does something bad and Igor punishes him by reading a tale involving a bratty girl named Melissa Screetch (voiced by Nancy Cartwright of Simpsons fame) who doesn't heed the warnings of adults (usually given by her mother) and gets punished one way or the other for it.
In season 2, Bill Kopp and Jeff Degrandis left the show and were replaced by former Animaniacs writer Paul Rugg. The series' format changed into more of a sitcom style with Igor, Dr. Vic, and Phil interacting with a variety of new characters, including a snooping next door neighbor voiced by Lost in Space's Johnathon Harris who was based on Norman Bates from the movie Psycho. He interacted with his 'immobile' mother by putting his hand over his mouth and talking into it. There was also a typical Transylvanian angry mob that was in fact a cheerful group of Beatles-esque hipsters. Most of these new characters were voiced by Paul Rugg, who also improvised many of their lines.
The only other backup segment to re-materialize in season 2 was Melissa Screetch in a new segment called 'The Melissa Screetch Show.' Whenever Melissa was disappointed with a friend or a family member, she'd go home and cover herself under her bedsheets where she pretended to host a show. She then had her transgressor on as a guest star and often did away with them in an ironic manner. This season also had a return to the B-Movie parodies in the first season, featuring just one cartoon about America being over taken by aliens who want to force America to use the Metric System. The lead alien was voiced by Billy West effecting a French Accent, making the segment a parody of American xenophobia.
The series ran for 2 seasons, until it was cancelled in 1998.