Note: I urge you to use the screening options when you make a post so you can manage the comments made to your post yourself. This might very well discourage trolls to spam posts as it would be a complete loss of time.
Also, the community joining settings is changed back to moderate. It sucks, but if it can prevent spamming(and I've never seen this much trolling since I'm on lj), then it's worth it. And putting your entries "friends only" will help aswell.
Thank you halloween fans,
Your friend and co-mod, hel the happy_skeleton