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.
YMMV: Resident Evil
Animation Age Ghetto: Or rather, "video game" ghetto: the original was one of the earliest M-rated titles to be released (and naturally, it got a warning label slapped on it for its violence). Alas, the idea of games potentially reaching older players (particularly on a mainstream console, as opposed to story-driven point-and-click games, or violent games on PC or more obscure consoles) didn't quite click with the parental groups and gaming outlets at the time, so it wasn't uncommon to hear of elementary-aged children buying and playing the game. Even the original action figures line by ToyBiz were marketed towards children (ages 4 and up) rather than collectors.
Badass Decay: A complaint about Rebecca Chambers, given that she seems much more capable in the prequel Resident Evil 0. Fanon and eventually The Umbrella Chronicles justifies this by noting that most of her team is dead over the course of the game, Billy Coen is gone, she's nearly out of ammo, and she's been awake for several days.
Dogs straddle the fence between this and Demonic Spiders, being hard to draw a bead on thanks to their speed —triply so if you're attacked by more than one at a time— but relatively easy to kill once you've knocked them down. They've remained a persistent nuisance in every game since.
Good Bad Bugs: The REmake had a glitch that let Jill get 240 of any type of Grenade Launcher ammo. Using this glitch with the flame rounds made ensuring no Crimson Head zombies popped up very easy. Fixed for PAL releases though, so those territories had to play by the rules.
The original PS1 version had it so that pausing the game right after you had hit an enemy with the knife would reset the knife animation while the enemy was still stunned resulting in the player being able to have Chris or Jill attack the monster again while they are unable to retaliate.
Hell Is That Noise: The heavy, plodding footsteps of a Hunter stalking you from off-camera is the most frightening sound in the original game by a wide margin. Right behind that is the telltale moan of a Crimson Head rising to its feet in the remake.
Hilarious in Hindsight: By the fifth game, Wesker is a nigh-invincible badass who can take down his foes with ease, dodge bullets, catch rockets with his bare hands, and even survive being dunked in lava...which makes it awesomely funny to see him frantically run away from a few infected dogs in the opening movie.
Also hilarious: His appearance as a special zombie enemy in the Sega Saturn port's "Battle Game", long before he reappeared in Resident Evil: Code: Veronica.
The first edition in particular is notorious for bad voice acting and cheesy lines. The two most memorable lines come from Barry Burton - referring to Jill as "the master of unlocking" after giving her the lockpick, then making a wisecrack about "Jill sandwiches" after saving her from the Descending Ceiling trap.
Mostly averted in the REmake, which actually throws out a Continuity Nod to the latter (Barry telling Jill she would have fit nicely in a sandwich if he'd been a few seconds later), and completely ignores the former (Barry simply tells her she'd make better use of the lockpick then he would).
Narm Charm: The cheesy dialogue is not without its fans.
Polished Port: The PC edition of the 1996 original lacks the extra goodies of the Director's Cut rerelease, but makes up for them by being completely uncut (which, despite the name, the Director's Cut largely wasn't), with the uncensored intro in full color and severed body parts remaining on screen rather than instantly disappearing. It also adds in an exclusive new costume for Chris and Jill that no other version has, and includes a fully automatic weapon for both characters —an FN Minimi for Chris and a MAC10 for Jill— that's powerful enough to make it even more of a Game Breaker than the rocket launcher. You could also hit a button to skip the "door opening" loading screens.
The Sega Saturn version wasn't exactly more polished, per se, but it did throw in two exclusive costumes of its own and introduced the first-ever "Mercenaries"-style battle mode in the series named "Battle Game" as well as introducing a couple of new enemies, such as the Tick (An altered Hunter), a second Tyrant that would attack you once you seemingly killed the first one, and the Battle Game-exclusive zombie Wesker and Golden Tyrant.
The Nintendo DS port subtitled Deadly Silence updated the character models and animation to bring them in line with the REmake's style, threw in another set of exclusive costumes, some tweaks to the controls (adding the quick 180 turn and a reload button), and added in a new "Rebirth" mode that features new puzzles, 1st-person knife fights, and a few more additions that make use of the DS hardware. Like the PC version, it also allows you to skip the "door opening" screens by hitting the action button.
Rescued from the Scrappy Heap: Rebecca's treatment in the remake changed her from the annoyingly chipper and somewhat daft character in the original game who seemed mostly oblivious to the gravity of her situation into a much more believable and sympathetic character who's fully aware of the danger she's in but still tries her hardest to soldier on anyway. Since the remake and 0 came out, most fans have gone from not really caring if she ever made another appearance in the series to now looking forward to the times when she does.
Scrappy Mechanic: One Dangerous Zombie mode in the REmake. The problem by itself isn't that it means an instant game over if you even accidentally attack the wrong enemy. It's that you can't turn it off, coupled with the fact that several areas of the mansion are very narrow hallways with few ways around.
The one saving grace: Once you leave the mansion and enter the guardhouse, Forrest never comes back.
They Changed It, Now It Sucks: The entirely new soundtrack for the Dual Shock edition of the 1996 original. Individual tracks ranged from passable if perhaps inferior to hilariously stupid (see Narm above), but there's a good reason Capcom decided to ignore them all and redo the classic soundtrack for the 2002 remake: some were okay, but none of them were an improvement.