Why do people like this so much? Even the director hated the second half!
I liked it too when I first saw it, in 1990, at age 18, but now, 32 years later, it's just so QUAINT and DATED now in every way. The Muschietti remake was a welcome breath of fresh air, if only for a different take on the story.
The whole 1990 production just screams "old-fashioned", with the cheesy TV music, cheap budget, melodramatic feel, and "suitable-for-all-ages" crap that doesn't belong to a Stephen King story. The script is muddled, focuses too much on characters that are boring, especially Audra, and is just too short. The less said about the ridiculous stop-motion spider crab creature at the end, the better.
The adult actors are average at best, I didn't like any of them. As for the children, I liked the Eddie actor the most, same as with the remake, but then I've always sympathised with Eddie.
Also, I didn't really care much for the 1960 (1950s) setting for the children, as it's just too far in the past as of now, which is possibly why it's dated so much, even if the book had it. The smartest thing Muschietti did was to bring both time periods forward 27 years to late 1980s and 2010s respectively.
As for Pennywise himself, which is the USP of the whole story, Tim Curry did fine with the script he was given, and is memorable, but is just as goofy as Bill Skarsgard in the movies, and also not enticing to smart children, ie Georgie and the sewer. When Georgie meets Pennywise, critics say that Georgie should be running away from Skarsgard, but there is a moment with Curry where Pennywise acts exactly the same, not "friendly all the time" as has been suggested. So I'd say that both Pennywises are fine in general.
As for the second half with the adults: pure melodrama. Even the director of the production hated it in the end, he said so on the DVD commentary. It's just dull, dull and dull. OK, so Muschietti's version is about the same, but at least they tried to make it better.
All in all, I like the IT story a lot but the Muschietti movies are more enjoyable, to me at least.