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: Princess Mononoke
Animation Age Ghetto: Claire Danes (voice of San in the English version) comments in the DVD's special features that she came into the film expecting it to be a children's movie.
Quite a few of the actors go on about how it felt like a real movie and not an animated one.
Broken Base: Other Ghibli dubs have fallen into this atmosphere, but viewers can't seem to decide if the Miramax/Disney dub is good in its own right or a watered down travesty to the original Japanese. Purists stubbornly declare it's the latter, but there are fans of the English dub.
Narm: Ashitaka rips off the arms of a samurai and heads off another with arrows. It is intended to make his curse more sinister, but it's also kinda funny and bloodless. Maybe done intentionally.
"FOREST SPIRIT! WE GIVE YOU BACK YOUR HEAD! TAKE IT! AND BE AT PEACE!"
Nightmare Fuel: Several examples, such as Nago's death, the transformation of the Forest God, and the assassins wearing the skins of dead boars.
One battle scene also has the Iron Town riflemen shooting a volley at a charging army. As the smoke is clearing you can hear a guy yelling "MY AAAAAAAAAAAAAAAAAARM!!" If you look real close, you can see the guy staring in horror at the ragged stump where his arm used to be.
Lady Eboshi's warriors wearing dead boar skin's and shuffling after Akoto, who doesn't understand the danger he's in, but San does and he won't listen to her.
The music that plays when the headless Night Walker is searching for his head.