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.
Denny is, supposedly, an intelligent if slightly naive boy about to head off to university but given his actual behaviour - following a couple upstairs and jumping into their bed mid-foreplay, hitting on Johnny's fiance and then telling Johnny, selling drugs when he's the adopted son of a banker - even Wiseau himself admits the film makes more sense if you assume Denny has quite severe socialization and learning difficulties.
Alternatively, it also makes sense if you consider him to be a budding, manipulative sociopath taking advantage of the kindness of two naive older friends (who, it should be noted, don't seem to mind things like Denny jumping into their bed mid-foreplay) and stirring up trouble for fun and profit.
The scene in which Mark tells Johnny a story about a woman that was physically assaulted by one of the "many" men she was seeing seems oddly sketchy if you pay close attention to Mark's facial expressions as he tells the story. Mark can clearly be seen slightly smiling after saying "she ended up in a hospital on Guerrero Street". His situation behind the break-up with the "unseen" Betty character also seem to be very suspicious after hearing this story out. Lastly, when Mark tells Lisa to get out of his life following Johnny's suicide he proceeds to hit her in far harder fashion than Johnny is accused of.
Greg's book makes clear that the bit about 'Guerrero Street' is an improv, because it's where Tommy Wiseau lived at the time (he didn't want anyone to know). Greg is laughing because of how he's pissing Tommy off. As he further goes on to point out, Tommy actually used this take in the movie because he couldn't be bothered to do another.
When Johnny laughs at Mark's story, it might not be because he thinks it's funny, but because he thinks Mark is making it up, hence him saying "What a story, Mark!" The Disaster Artist seems to contradict this interpretation, since Tommy Wiseau had to be told he shouldn't laugh at domestic abuse.
Claudette's dialogue makes much more sense if you assume she's a drama queen and an attention whore - traits that clearly run in the family. If, as she claims, "nobody listens" to her, this is probably not the first time she's made up something like breast cancer, hence Lisa's calm reaction.
The Newgrounds flash game gives an extended ending: Johnny is an incorporeal alien sent to Earth to learn earth customs. When he kills himself, he's merely releasing his alien form to return to the mothership and, provided the player collected all the MacGuffins, turns Earth into a giant spoon.
"I Will" is pretty good too, for a cheesy love song.
Pretty much the entire soundtrack is pretty good. It's rumored that this was the only part of the film Wiseau had no control over.
Big Lipped Alligator Moment: Several but first and second prize go to the scene with Mark shaving and the football games respectively. They're so pointless that even Tommy Wiseau and the other actors don't know what the point of those scenes are. And Wiseau's the freaking writer.
Captain Obvious Aesop: Wiseau claims the message of the film is "If a lot of people love each other, the world would be a better place to live."
Considering he says this in the context of Denny confessing his love for Lisa, it's also a Broken Aesop.
Cult Classic: The Room continues to be screened in L.A. and other cities to this day, thanks to becoming a cult phenomenon. Not really surprising given how fascinatinglybizarre it is. Tommy Wiseau himself comes to these screenings to discuss the making of the film, though he does not reveal much....
Darkness-Induced Audience Apathy: Johnny is a wuss, Lisa is incredibly stupid and / or callous, Mark is a douchebag and / or an idiot, and Denny has drug problems and a very creepy relationship with Johnny and Lisa. The writing and acting don't help, either.
Dude, Not Funny!: Johnny laughs after hearing the story of a cheating woman getting beat up to the point that she had to go to the hospital.
Ensemble Dark Horse: Both "Doggie" - the dog that is lovingly referred to as such by Johnny at the flower shop, and Chris-R seem to be considered the only good actors in the film, but that is not really saying much.
As utterly pathetic the Wimp Fight between Johnny and Mark was, Wiseau really was hurting Sestero as by the end of it, the latter had bruises all over his arms and wrists from the former's hands, which have apparent "cyborg-like strength".
The reason why Peter was acting kinda dazed and touching things a lot in one scene was because his actor had suffered a concussion and Wiseau wouldn't let him leave for treatment of it.
Mark briefly mentions breaking up with his girlfriend during the rooftop scene. Turns out Greg had just broken up with his girlfriend, and Wiseau wrote that in the script the day it happened.
Greg Ellery clearly knew what kind of movie he was in and his melodramatic performance as Steven brings life to the plodding birthday party.
Scott Holmes (Michelle's boyfriend Mike) spends the entire movie aping Jim Carrey, clearly playing for whatever sympathetic laughs he thinks he might get.
Dan Janjigian's performance as Chris-R is delightfullyover-the-top. Some YouTube commenters have jokingly theorized that he was a real drug dealer who just started pointing a gun at Denny and not an actor at all.
According to script supervisor (and possible ghost director) Sandy Schklair, everyone knew full well what kind of movie they were making. Well, everyone except Tommy Wiseau.
Here's the background for that scene: Kyle Vogt (Peter) had other work at the time, and so could only be involved for so long. However, despite repeatedly reminding Tommy that he had to leave production, they weren't able to finish his scenes and instead of filming the party with Kyle, Tommy insisted on the "football in tuxes" scene. It makes the line even more hilarious in hindsight.
Ho Yay: There's a bit between Johnny and Mark in the beginning, but it's quickly dropped in order to make room for the love triangle plot that drives the rest of the movie.
Johnny's reaction to hearing that Mark is dating a married woman could easily be interpreted as jealousy.
How about all the attention Johnny lavishes on Denny?
Johnny and Mark tossing a football around in the park seems much more romantic than any of their interactions with Lisa, since all they do with her is talk and have sex.
Marty Stu: Johnny. Throughout the movie, he never actually does anything, other than have sex, buy some roses, and throw a football around. Everyone else's characters are defined, primarily, by their relationship to Johnny, and he somehow managed to land a major hottie, at least until he Ate His Gun.
Also, barely a scene passes without someone saying how great Johnny is (with how beautiful Lisa is coming a close second). The man can't even buy flowers without being told how wonderful he is.
One-Scene Wonder: Chris-R. He's not the only one, though. Characters drift in and out of the film like a fever dream.
One True Threesome: Lisa, Johnny, and Denny seem to have a suspiciously close relationship regardless of being surrogate family. Denny even comes and hangs out in the bedroom with them for a while when they clearly are working up to sex.
Nothing between the second sex scene and the birthday party has any actual effect on the plot.
There were at least two or three establishing shots during one scene that took place in the same setting.
Probably the most obvious form of padding used is that of having characters essentially repeat scenes with only a few details changed. This is especially obvious when it comes to Lisa and Claudette, whose conversations with each other are always about virtually the same thing, and with Johnny and his friends tossing the football back and forth.
One odd scene from the middle of the party lasts only a few moments, and is just a shot of the city with the theme music playing. It has no bearing on anything, and might have been used just to denote that time had passed.
Parody Retcon: The director and star claimed his film was actually a "black comedy" after it became the So Bad, It's Good hit of 2003. Trailers were even hastily edited to reflect this. No one was fooled, except maybe Wiseau. The rest of the cast and the script supervisor knew exactly what they were making.
The Scrappy: LISA. Everyone in the movie's annoying due to their bad acting and/or stupidity, but she really takes the cake. Her annoying, repetitive mother Claudette and idiot not-boyfriend Mark come in very close second.
So Bad, It's Good: The film has become a cult classic for being so bad it's good - no, more like So Horrible It's Epic.
Squick: The rather graphic sex scenes between Lisa and Johnny. We see far more of Wiseau's particularly unappealing body than we need to. Actor Greg Ellery states that the Squick goes behind the scenes as well. The actress who plays Lisa was only 23 years old. Wiseau was 47.
More to it than that. Apparently Wiseau wanted it to be realistic, so he actually was completely naked while they filmed that scene. That's why he seems to be having sex with her naval - he wanted to make sure he didn't accidentally...erm, get it in there.
Worse, according to cast and crew, Tommy had... body odor issues.
There's one scene where Lisa's neck starts strangely spasming!
What would also have helped is if certain scenes were used to add emotional depth to the film rather than serving as padding. In particular, the drug dealer scene could have been more significant had it effectively been tied into the overlying plot rather than solely being used as an only loosely connected Chekhov's Gun to Johnny's suicide, and the issue of Claudette's breast cancer could've gone somewhere as well.
Dan Janjigian as Chris-R. As detailed in The Disaster Artist, the guy went as far as applying Method Acting to his role...despite being the only person in the cast who wasn't a professional actor and him only doing it as a favor for his roommate. As a result, he became a One-Scene Wonder who gives one of the few convincing performances in the movie.
Also as detailed in The Disaster Artist, Carolyn Minnott as Claudette. She had always wanted to act, and this was one of the only parts she could get. As such, she gave it everything she had, even nailing a scene right after being hospitalized for heat stroke.
Unfortunate Implications: As pointed out in The Disaster Artist (written by one of the co-creators after the film came out), all the major female characters seem to be capable of is gossiping, drinking, shopping, and/or having sex.
Unintentionally Unsympathetic: Johnny, who comes off as creepily obsessive and a douchebag rather than the model husband Tommy Wiseau intended him as. For instance, he laughs at the thought of a woman getting beaten up and going to the hospital (and it's not one of those awkward, WTF "are you serious?" laughs, we think), and later on, while claiming he never hit Lisa, he shoves her onto the couch when she is ready to walk away. This has Reality Subtext as revealed in The Disaster Artist. Wiseau actually had to be told by the crew that domestic abuse wasn't funny, as he was oblivious as to why he shouldn't laugh, but it stuck because they couldn't get a better take of the scene.
Vanity Project: While an indie project that usually requires filmmakers to wear multiple hats, Tommy Wiseau still managed to do this with his little debut film which he wrote, directed, starred in, produced, edited, etc. The opening credits start off with his name repeated multiple times before you see another name.
Wangst: Johnny is especially guilty of this in his dialogue.