I got the opportunity to watch the recently unearthed R-rated version of this movie (the movie was cut for its original theatrical release in order to get a PG rating). So I was expecting the movie to be somewhat explicit in either gore or sexual material. But I was surprised. This original cut shouldn't have got an R rating back in 1970! The only sexual material is one (brief) scene of toplessness, and when it comes to violence there are only a few drops of blood and a couple of scenes of hangings directed in a restrained manner.
Still, despite this lack of exploitive material, the movie could still have been a decent supernatural shocker. But it isn't. It's very slow moving, and with a LOT of chitchat to pad things out. So I would say the PG version is the version to seek out if you really want to see this movie - because it's shorter and therefore easier to sit through.