How do I disable supernatural?

I have found that some options, and I don't know which ones, are save (or maybe world) specific. So I always check my options if it's important to me. I've noticed this because most of my saves have multiple worlds in them and I sometimes wonder why things are happening that I thought I'd turned off but when I travel to a different world in the same save they are on again. But revert to being turned off when my sims return to the original world.

Disabling all of the occult types will stop the game turning your townies into supernaturals, but if you already have supernaturals in that world it is possible some of them might turn others to their occult state. I have had this happen only once that I know of, and it was in Moonlight Falls which is the world that came with Supernatural. One of my sims got turned into a vampire when I changed households for a short time. I cured her easily enough, so it wasn't a huge problem but it did make me wonder how it happened. I finally worked out one of the vampires that came with the world must have done it to her. If it had happened to a townie that I wasn't playing at all then I probably would have never noticed.

I don't tend to worry about the zombies so haven't changed the phase of the moon but that is the only way I know of that will keep zombies away. They only arrive when it's a full moon.

I hope you are able to find a solution that suits you.