I think that Ghostbusters was the first movie I saw multiple times (five times) in the theater, and I was a big fan of the cartoon as well. It was called The Real Ghostbusters to distinguish it from a different, suckier cartoon called The Ghost Busters that was on during the same period and that had nothing to do with the movie. I remembered this being a pretty well-written show, but I was still surprised, looking over the episode list, to see how many of them were actually written by authors whose names I recognize (notably J. Michael Straczynski, Michael Reaves, and David Gerrold). There are three episodes I remember in particular, and I'm pretty sure that's because these were some of the scariest ones I saw.
In the first of these, "The Thing in Mrs. Faversham's Attic," the Ghostbusters are called to the home of an elderly lady named Mrs. Faversham who complains of sinister thumping and laughter that emanates from her attic. The Ghostbusters investigate, and discover that the attic is impossibly large and that every object in the attic seems suffused with malicious intelligence. Peter conducts a conversation with a creepy coatrack who demands that Peter bring him "Faversham."
When negotiations break down, the Ghostbusters attempt to flee the attic, only to find that the exit has vanished. It seems that the evil entity controls this space so completely that if it doesn't want there to be an exit, there isn't one. Fortunately the Ghostbusters are able to distract it enough with their proton beams that the exit reappears, and they're able to escape.
But why, they wonder, would a being of such obvious power not simply follow them down out of the attic? After further questioning Mrs. Faversham, they deduce that her father had summoned this evil entity in hopes of bargaining with it for wealth, and when that hadn't worked out he'd performed a spell to trap it in the attic.
Eventually they're able to trick it into manifesting itself, and are able to capture it in one of their ghost traps.
The next episode I really remember, and definitely the scariest one, is called "The Boogieman Cometh." In this one, a pair of children attempt to hire the Ghostbusters to rid their closet of the "Boogieman." Peter is skeptical, but Egon reveals that he too was once a victim of the Boogieman, who's a sort of psychic vampire who feeds off the fear of children. And I don't blame those kids one bit, because the Boogieman as drawn here still makes my skin crawl:
The Ghostbusters eventually trail the Boogie Man into his lair, an Escher-esque realm where gravity and perspective mean nothing, and which is full of doorways leading into the closets of the Boogie Man's various victims.
I sort of wonder if anyone who worked on Pixar's Monsters, Inc. had seen this episode, because there are a lot of similarities, right down to the climax -- a chase scene that goes into and out of different closets and bedrooms.
The last episode I really remember is called "The Man Who Never Reached Home." In it, the Ghostbusters have stopped at a diner when Ray encounters a man in a horse and buggy who asks for directions to Providence. Ray gives directions, but the man refuses to believe him. The man has been riding all night, he says, and yet he never seems to get any closer to home. He then flees in terror, just ahead of a mysterious cowled horseman, who rides off after him.
A diner employee reveals that the guy in the buggy is Queg, a local man who disappeared over a hundred years ago and who reappears periodically, still trying to find his way home. Ray determines to help this poor ghost. The Ghostbusters manage to track down Queg, and Ray urges him to step down from his buggy. This leads Egon, who's studying a ghost-meter, to remark, "Ray, I don't think he can get down from the buggy. It and the horse are powerful class 9 spectres. Queg's merely a class 6. He's not strong enough to resist them." I've always loved that line.
In the end, Ray convinces Queg to turn and face the rider who has harried him all these years, and Queg agrees. In a flash of lightning, Queg spies the face of his pursuer for the first time:
"That's my face!" Queg cries. "It ... it's me. I've been running away from ... myself." Holy shit, Real Ghostbusters. You just blew my mind.
Queg summons up the courage to face himself, and is then free, after all these years, to finally go home.