These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The sudden giant snake in the 70s version. If dinosaurs/other giant animals showed up earlier it wouldn't be so odd.
Don Simpson's 1993 comic, adapted from the Delos W. Lovelace novelization, originally had a scene it where Kong destroys the Hindenburg. It got cut after Simpson decided it was in poor taste and too bizarre.
Designated Hero: Jack in the 2005 version. Most of the crew's deaths can be traced back to his obsession with saving Ann, and all the while, he constantly gets upstaged by both the titular ape and the snooty actor he didn't like.
His decision to draw Kong away from Times Square probably causes more death and destruction than if he'd just let him be.
Denham in the original. The trip is his idea, as is the choice to bring the ape back to New York, where it promptly wreaks havoc and causes more deaths but he is never called out for his actions.
Ending Fatigue: One of the major problems many have cited of the 2005 remake was that many scenes went on far too long than needed, and its running time of over three hours wasn't really warranted.
Fair for Its Day: Yes the original Charlie the Cook is pretty cringe-worthy but this is the 1930s and the guy is the first to notice Ann is missing, is willing to help go after Ann, and brave enough to swing his cleaver at a very angry dinosaur in the sequel. Plus in the same sequel he isn't excluded from the spoilers either.
First Installment Wins: While there have been many sequels and remakes, the original 1933 film is the version most often spoken of by fans.
Harsher in Hindsight: The entire battle at the World Trade Center in the 1976 film is much creepier in the aftermath of September 11th.
It Was His Sled: There aren't too many people who don't know how this story turns out.
Magnificent Bastard: Dino De Laurentis is a meta example. During the film's production he knew damn well that no one would believe in a giant 40 foot gorilla and would constantly look for mistakes to make the illusion even more fake. So what does he do? Well he instead built a giant 40 foot robot Kong and exclaimed that the robot was going to be the monkey, not revealing that the robot was only going to be in the movie for a couple of seconds. And when critics saw the movie, they tried to show a distinction between the robot and the giant ape suit. The kicker? They got the comparisons wrong. So De Laurentis fooled people into believing an illusion with another illusion.
Misaimed Fandom: For the 1933 Kong at least, to some extent. He does kill quite a few otherwise innocent people on both Skull Island and in New York when he breaks loose. He was meant to be sympathetic, but not to the extent that you should ignore his destructive qualities.
Narm: Parts of the original as well, including the most blasť declaration of love ever.
No Problem with Licensed Games: Peter Jackson's King Kong: The Official Game of the Movie, generally thought to be one of the better licensed games out there.
Son of Kong, while inferior to the first film by far, still manages to entertain. It helps that the cast has three major returns in it (Mr. Denham, the Skipper and Ethnic Scrappy Charlie the Cook) and Willis O'Brian returns for the special effects.
The snake from the 1976 version could also qualify, looking very stiff, robotic, and lifeless compared to the fairly realistic animatronic face and hands built into the Kong suit.
On the subject of Kong '76, there the the very literal failure though the highly publicized full-scale mechanical Kong armature, designed by Carlo Rambaldi. Leading to makeup legend Rick Baker designing and donning the ape suit used for 95% of the movie. The mechanical Kong was only in one scene -his New York unveiling- and boy, can you tell.
Even the version of the Kong arm which was used in the (now retired) Universal theme park attraction was notoriously fake-looking.
They did build a to-scale animatronic of Kong's head and shoulders for the 1933 film. It has several quick appearances, the most notable being Kong's unveiling in new York and during his rampage in the native village (the close-ups where a villager is in his mouth). Though it was pretty motionless (only the eyes and mouth could move, and limited at that), it still worked fairly well by comparison.
While the 2005 version has some spectacular work done on Kong himself. Most of the scenes on Skull Island look rather hokey and rushed. The Brontosaurus chase in particular, due to how obviously green-screened the actors in those shots are. Some of the New York scenes also look like they came from a video game.
For 1933, anyway. The stop-motion effects were so impressive they got a kid named Ray Harryhausen interested in making that a career. There are still cinemaphiles and effects experts impressed with how Willis O'Brien made his effects.
The 2005 film has amazing CGI/motion capture effects. It rightfully won the Oscar for Visual Effects (it also won for Sound Mixing and Sound Editing and was also nominated for Art Direction)
What Do You Mean, It's Not for Kids?: While the 2005 version is probably a bigger target, even the original 1933 version is subject to this. Not only are there a lot of death scenes, they're surprisingly brutal! The stereotypical natives and the scene where Kong undresses Ann do not help.