A dog is strangled.

Not in the shorter version (1h 45m).

Teenage girls smoke a joint in the car

It's strongly implied in one scene that one of the main characters has an alcohol problem.

Laurie fends off Michael by jamming a coat hangar in his eye hole. It's quick, in the dark, goreless, and doesn't linger on it for long.

There are a lot of knife kills.

Michael drops a handful of bloody teeth but the death and tooth removal are not shown.

Laurie cracks her knee falling down the stairs

Someone gets their fingers shot off with a shotgun.

I'd call it psychological torture to force someone to share a backseat with an unconscious psycho killer.

Twice throughout the movie a head is squashed, one being possibly the most gory death in the franchise.

Yes, but not in the typical sense. Allyson, Laurie's granddaughter, is put into the back of a police car with a passed out Micheal, while his just as nutty out of his mind doctor kills the cop and takes over the wheel and starts driving to Laurie's bunker, to "awaken" Michael and see him in action. To the obvious distress of Allyson.

You see a child get their throat crushed by Michael on screen.

In the original Halloween, no parents die, unlike what others say.

Someone who's in a relationship kisses someone else at a party. The partner sees it, and there's a confrontation.

In a flashback at the beginning of the movie, Michael is dressed as a clown as a child

Not in the shorter version (1h 45m), but I believe there is one in a deleted scene or a longer version,

Actually not as many or as bad as you might expect.

Michael puts a white sheet on to look like a ghost

A prison/hospital for the criminally insane.

A knitting needle is used as a weapon against the killer.

A prison/hospital for the criminally insane.

So many. Main character has severe ptsd agoraphobia and anxiety. I don't know why someone answered no.

A girl is trapped in the back of a cop car with a knocked out Michael Myers next to her and has no way of escaping. I don't know why people are answering no.

The journalists do kind of fumble it up when interviewing Laurie, and reactions/comments regarding Laurie's mental health aren't exactly handled with tact.

Yes, but in one scene in particulat bright police lights flash for quite a while in the background.

Bare b*****s are shown briefly, 2 teenagers start to hook up but are interrupted by the kid the girl is babysitting, references to s*x throughout the movie

A traumatised person with agoraphobia and paranoia is talked about disrespectfully because of how she feels and acts.

Dad makes a joke about his daughter ending up fat and on drugs if she marries her boyfriend, whose family has a bad reputation.

Comment to grey26's comment: By no means can we be sure that Myers escapes in the end. In fact, comment sense and normal experience tell us that he must be dead, only there's a little teaser in the form of a discreet sound at the very end (which I personally didn't even notice; I just read about it in IMDb trivia afterwards).

Michael kills his sister, Judy

Almost every kill by Myers has tons of blood.

Multiple people are strangled

Sort of. one on a wall and another on a fence, but they are not the traditional rope/cord hanging.

We're told throughout that one of the adult characters grew up in an atmosphere of paranoia, constantly being prepared and trained for a possible future encounter with a murderer. At one point, the parent who did it admits that raising their child that way was wrong. I must stress, however, that the parent did it out of a very understandable fear for the child's safety, and hence with good intentions.

However, someone does fall from the upper floor of her house, to the ground level.

A sort of bus.