These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Name's the Same: Apart from the horror theme, bears no resemblance to the coin-op or pinball machine of the same name.
Nightmare Fuel: Johnny will need a lot of counseling once he is done with his adventure. 10 year old kids are not meant to fight zombies nor to see spikes with entrails still on them.
Suspiciously Similar Song: Several. The title screen sounds similar to "The Monster Mash", the first stage contains the intro to "Toccata and Fugue in D Minor", the penultimate stage of episode 2 has a small snippet from "In the Hall of the Mountain King", and the fight music against Igor bears similarity to "Flight of the Bumblebee".
That One Level: The two swamp levels in episode 3 are probably the hardest ones in the game. Expect to use that extra lives cheat a lot.
Stage 3-3 in particular contains some of the hardest jumps in the game: onto moving platforms that are very difficult to stop incoming.
For the pinball:
Fridge Logic: The Putting the Band Back Together premise makes less sense when you consider that Frankenstein has yet to assemble his monster, and some of Igor's lines imply that he's not simply relocating old parts.
That One Level: Activating Lyman's Lament the normal way requires 40 shots to the scoop in one game. This won't happen until you have near-perfect control of the ball and can effortlessly pass the ball between flippers.