I'm not going to spoil the film here, as I already wrote the full plot summary on the page Goosebumps 2: Haunted Halloween.
Anyway, I really liked the movie, it was fun, exciting, and just plain awesome! I wouldn't say it's better than the first one, but it was more fun to watch than the first one, in fact, I think it feels more like a Goosebumps story than the first one!
The monsters in the film are cool, I like all the new monsters, and the old ones, which are Slappy, The Werewolf, The Abominable Snowman, The Mummy, The Scarecrow, and the Lawn Gnomes!
I loved the cast, Wendi McLendon-Covey and Ken Jeong were hilarious! The rest of the cast were good too.
My only spoiler here is that the end credits features a montage of the monsters in the film which I thought was epic!
And one more thing, The Gummy Bear Song is not in the movie!
Overall, I think Goosebumps 2 is awesome! I recommend you see it!