Here is a collection of movies that were released with a PG rating, most of these films came out in the 1970's before PG-13 existed but there are a few films that pushed the limit on what was accetable for movie.
Devils Rain (1975)
A satanic cult leader is burned alive and vows he will return. He wants a satanic book that was stolen by the ancestors of those who betrayed him. The movie features many sequences were people melt in the rain.
Jaws 2 (1978)
Like the first Jaws movie, Jaws 2 does scare the audience with a terrifying shark that gets more screen time. The film does feature many shark attacks that do show people being dragged under but not as much blood is shown as the first movie. There is plenty of bad language and some scenes of teens making out.
Tales From the Crypt (1972)
A Britsh made anthology movie that features five people who are shown the manner by which they will die. The film features acts of violence against each of the five, scenes of a man hanging, as well as limbs and body parts being cut off or opened. The film evokes the eeriness of the dark comic book it was based upon.
Twilight Zone the Movie (1983)
This anthology film based on the popular 60's TV show does feature segments that can scare young children and some audience members. Most of the violence is not bloody, but there are jump scares and surreal images of terror that will unsettle you. One segment does deal with racism, so there are racist insults uttered by characters. The anthology is well made and a great tribute to the original series yet there was controversy over the deaths of some actors in a segment was not removed.
Something Wicked this Way Comes (1983)
Disney made this movie and based on a novel by Ray Bradbury. The story centers on a mysterious man who comes into town with the circus and offers people something they desire yet he is out for souls to populate his circus troupe. For a Disney movie this a surprisingly creepy movie, with scenes that may scare young children. Plus there are some scary looking clowns, and that will give some a few chills.
The Legend of Hell House (1973)
A group of paranormal investigators arrives at the Belasco mansion to determine if the house is indeed haunted. Unlike The Haunting from a decade previous, The Legend of Hell House is more violent with people dying, brief glimpses of mild nudity and some instances when someone receives bloody injuries from a ghostly attack.
Burnt Offerings (1976)
A family moves into a large Victorian style mansion for a small sum yet discover that the house comes with some dark secrets that begin to affect everyone who lives there. The film has some terrifying moments that are enough to scare younger viewers and plenty of implied terrors that will scare everyone else. Burnt Offerings is best known for the creepy chauffer who may very well be the most terrifying driver in horror movie history.
Race With the Devil (1975)
Two couples on a road trip in an RV witness a satanic ritual and then find themselves being hounded by the members of the group looking to silence them. The movie features a human sacrifice with some blurred nudity, bad language as well as some animal deaths that may be unsettling. Race With the Devil is the type of movie that PG-13 was created for yet in its day Race With the Devil got by with a PG.
Picnic at Hanging Rock (1975)
A Valentine's Day picnic for students at an all-girls school turns tragic when three girls and a teacher disappear into a nearby rock formation. The movie builds an atmosphere of dread with its dreamlike sequences and moody pan flute music. The girls who disappear do so in a hypnotic-like state where they almost seem aware of the mysterious circumstances that are about to occur. The film is not horror movie scary but is unsettling and s mysterious given the fate of the girls is never revealed.
The Stepford Wives (1975)
Moving into an exclusive community, a liberal-minded lady is surprised at how perfect the other ladies are and begins to suspect that something isn't right when the one outsider she befriends suddenly behaves more like the others. The Stepford Wives is a chilling tale that will scare some with its creepy plot and shocking conclusion. The movie also contains some female nudity, sexual situations, some violence, profanity and other adult vices.
Arachnophobia (1990)
With so many people having a natural fear of spiders this film was the perfect nightmare fuel for this common phobia. A doctor with a fear of spiders finds some people are turning up dead after a deadly spider was accidentally imported. With thousands of spiders in the film, it is no wonder so many people were turned off this movie. Thankfully the movie offers plenty of comic relief with John Goodman as the exterminator.
Gremlins (1984)
Joe Dante's blockbuster film was marketed as a family friendly film with cute little creatures that turn into mischievous demons when the rules of their care are not followed. Families and critics were surprised at how dark the movie was, and the gremlins cause a series of accidents that result in the deaths and injury of many of the people they encounter. Gremlins are killed in some violent ways, yet these deaths are played off with a slight bit of campiness. Gremlins is a great film and deserved all the praise it earned, the only issue it genuinely deserved was criticism for how violent the film was given the PG rating.
It's Alive (1974)
A woman gives birth to a mutated human that aggressively murders everyone in the operating room and escapes. A search is conducted for the escaped child while the father seeks answers to why his child was deformed. It's Alive features many dead bodies scattered through the movie with most having their throats slashed. Given how bloody the bodies are when they are shown it is surprising to see a PG rating.
Invasion of the Body Snatchers (1978)
The remake of the 1956 cold war thriller was a film that spooked audiences with its premise of a population being replaced that gave enough fears to a nation already jaded by government conspiracies. The movie does feature female nudity, violence committed on the clones and a nightmare fuel moment with a dog that has a human face. Invasion of the Body Snatchers is a rare remake that surpassed its original film.
Poltergeist (1982)
The movie Poltergeist was a film that many audiences felt was improperly rated at PG. The movie was directed by Tobe Hooper who was best known for the Texas Chainsaw Massacre yet having Steven Spielberg probably helped it slide away from an R Rating. Poltergeist is a scary movie that had children being threatened by tree branches, a gross sequence with a guy peeling off his face and of course the youngest son almost being killed by a toy clown. Many critics feel the movie deserved an R Rating and the arrival of the PG-13 rating a few years later was probably from the backlash of people who felt Poltergeist was too scary to be rated R.
Jaws (1975)
The first big summer blockbuster was also one the scariest movies ever made at the time. Jaws gave audiences nationwide enough fear that many people to this day refuse to swim in the ocean. Jaws does show brief nudity, has bad language and some of the deaths are pretty frightening for a movie that is rated PG. Jaws is without a doubt one of the scariest movies of all time and is rated PG.