I would agree that The Two Towers is probably my least favorite of the trilogy. The epic battles (like the Helms Deep throwdown that seems to take a majority of the last four hours of TTT), while enjoyable, aren't the reason I like the Lord of the Rings movies. Not that those parts aren't good in their own way, they're just not as interesting to me as the overall quest to destroy the ring.
Luckily, while Two Towers had the most human on orc aggression, it also had its fair share of memorable scenes.
Smeagol vs. Gollum
As Frodo and Sam sleep unaware a few paces off, two sides of a split (shattered?) personality debate over what exactly to do with them. One of the two has warmed to the pair, and wants to assist them. One of them wants to smash them over the head and takes (er..take) back the 'Precious'. Naturally, an argument ensues.
The "same body with two minds having an argument" trope is surprisingly played out, but this is my favorite example of it (yes, better than Fight Club). Andy Serkis delivers here in a big way. He makes Smeagol into a living, breathing wretch (and, more importantly, he turns Gollum into a malevolent soul, stripping at least that persona of any of the sympathy he might have accrued), adding facial expressions and that weird little hop that defines the character. It's been said that it's a shame that he won't ever win any Oscars for the amazing motion capture stuff he does, but he gets the next best thing.
He almost singlehandedly wins eighty-third place in a random "best scenes of all time" list.