Primarily, the '80s is a good place to find examples of movies that were made for-or seemed like they were made for-kids that are either too dark or too scary for its audience in the 2010s. However, there are a few exceptions that float in this movieland purgatory.
You're not bringing your two-year-old to see Pulp Fiction, and I'm not going to watch The Wiggles Movie on my own-today.
I'm not going to pretend there's 'a fine line between kid's movies and adult's movies.' Typically, it's an impenetrable wall.