Here I often think, what is the best trollology movie? It's hard to say at once which film is the best... I mean, on the one hand we got our first glimpse of Middle-earth in """"Fellowship of the Ring"""". And the moment when the Balrog appeared in the dungeon in Moria and scared the orcs away - I have watched it hundreds of times.
In the second part we saw the great battle of Helm's Deep. At the time, it was the coolest battle I've ever seen. And I was also honestly annoyed by the Frodo and Sam episodes in parts 2 and 3... Plus there's also the moment with Gandalf showing up in Fangorn.
In The Return of the King it's Tuck's vision in the palantir, the moment with the signal lights of Gondor, the moment when Gandalf magically drove the Nazguls away, Aragorn's march to the dead, when the Rohirrim lined up and rushed into battle, etc.
What's pathetic is that none of the movies have information about Ancalogon -
https://www.thetolkienforum.com/wiki/Ancalagon
So I think part 1 is the best part.