The battle scenes are very impressive given the early-2000s GCI work. Many of the action sequences feel like a fitting payoff after longwinded portions of the first film, but the dialogue is rather forgettable at times here.
This would probably be my second favorite in the trilogy if we could just edit out Peter Jackson's ill-advised attempts at humor, like the Gimli short jokes and Legolas surfing down a flight of stairs. Otherwise, the battle at Helm's Deep is as good as action gets in Lord of the Rings: not as epic in scope as the battle in RotK but much more intimate and personal of a fight, and therefore more exciting to watch.
Significantly spottier than the folksy, charming first one, but it gets by on passion. There's a lot of high-fantasy mythologizing that would make me roll my eyes in another film, but it's earnestly sold and you can sense real belief behind the filmmaking. With almost 15 years of hindsight, Gollum does seem thin, but there's something so captivating, low-fi, even classical, about the way the creature was realized.
Surprisingly, a dud. Endless grey monologues, pointless side-plots, key uncharismatic performances from, to start with, Hill and Otto. None of the wistful earthiness and even passion of the first film (perhaps due to the absence of Bean and Holm). Brad Dourif's small role as Grima Wormtongue is so good that the film plunges into dullness on his departure. The reliablity of Wood and Astin bring the only solidity.
The strongest of the three - a perfect balance of relational, emotional, and plot-driven drama. Much more subtle than the others, with Andy Serkis and Bernard Hill stealing scenes left and right and powerful performances also by Viggo Mortensen, Miranda Otto, and Sir Ian McKellen. A beautiful climax that still makes me weep after 10 years of viewing.