Yeah "Laughing In The Dark" was always one of the most popular and it's a pretty great concept. They actually did another creepy clown episode later called "The Crimson Clown" which isn't as good but also one of their better episodes (the rotten little kid that's tormented by the clown is one of the show's better characters).
Yep, "Shiny Red Bicycle" was always one of my favorites. Dude's dead brother coming back to haunt him. "Frozen Ghost" was indeed another good one- bonus points for Clarissa.
"Jake & The Leprechaun" is indeed hokey but a lot of the hokey episodes are really fun. "The Bookish Babysitter" is a perfect example.
They had multiple episodes with unhappy endings- "Pinball Wizard" definitely qualifies.
In general, those first 3 seasons hold up really well. Haven't bought any of the later seasons because I'm only interested in the ones I actually remember from childhood.