I loved seeing it as a kid. Things like the Garthim were certainly scary. But there are things about seeing stuff through the eyes and mind of a child that you can't replace. You many not understand things as much as a kid, but you are far more OPEN, and everything is just so much bigger and more wondrous. If I had never seen The Dark Crystal until my teen or adult years, I would still love it, but I don't think I would have the FULL appreciation for it that I have having first seen it as a small child. It's a film that's "been with me as a I grew up", so to speak, and thus seeing it over the years, you notice new things and get different things out of it. As a child, I just soaked it all up, as the spectacle it is. I didn't "understand" it all, but it was an adventure and world that certainly touched my life, permanently.
Jim Henson's finest work, bar none. I do believe he felt so as well.

The Gargthim did give me nightmares when I was a kid (and when I rewatched it college), but I still loved the movie.
All glory to the Hypnotoad

But what if you had had an adult watching it with you and getting you to dwell on the positive things in the movie? You might not have had too many nightmares from it.

You know, it's really interesting. I'm probably one of the most sensitive people alive when it comes to scary stuff and dark stuff, but for some reason, though yes, this film is extremely dark, it didn't frighten me or give me nightmares. I think I was 7 or 8 when I first saw this on cable (not long after it left the theaters), and I fell in love with the movie.

This message has been deleted.

I've seen this movie more times than I can count. I was in the eighth grade when I saw it in the theatre. Still, even though I know it's coming, when Fizzgig jumps out of the bushes screaming at Jen the first time, I still jump every single time!

This message has been deleted.

The first time I saw this was as a little kid and I loved it
The Truth is Out There.