Karen and I went out with Sev and Lisa yesterday to finally see Return of the King, and I came away with a number of life lessons (spoilers galore).
First, if you defeat someone, kill him at once or else he'll come back to screw with you again. This kept happening: Denethor, Gollum, Saruman — except you'll have to wait for the special edition DVD to see that example, since they cut out the entire end plot about Saruman and Gríma Wormtongue escaping from Fangorn and doing their best to ruin the Shire in a blatant allegory about modern industrialism (or so it would be if Tolkien didn't insist that he hated allegories, and nothing in Lord of the Rings was allegorical). But no, they had to give us twenty minutes of Hobbits hugging goodbye instead.
Second, if you're building a huge mountain fortress, make sure there's no safety wall on the very top level. That way, burning stewards can run unimpeded off the edge. Speaking of mountain fortresses...
Third, if you have got a huge mountain fortress, and an army of Orcs is attacking you, how about getting the women and children inside and away from the windows? For one thing, they get in the way of your soldiers if they're out on the "streets"; and for another thing, they'll be a lot safer if they're inside, and away from the easily-breached stone walls. And speaking of which...
Fourth, if one boulder from a catapult can take down an entire stone tower, but your wooden door can withstand a huge flaming battering ram for an astonishing amount of time, consider building your fortress out of wood. Credit for that observation goes to Severin, who also noticed that the men of Mínas Tírith had no problem loading fourteen-ton blocks of masonry into their trebuchets, and that Gandalf's only apparent magical powers were the ability to make his staff glow and keep himself utterly spotless when all around were grimy.
Fifth, if you want to kill Orcs, just send in some tasty food and they'll kill each other trying to get it. This happened in The Two Towers as well.
Sixth, Falls from great heights are never fatal in Middle Earth. Gandalf survived his fall in Moria (as did the Balrog), Gollum survived his fall into the chasm outside Shelob's lair... the only reason Denethor died (well, I assume he died, since he didn't pop back up again) is that he was also on fire. This is clearly the reason Gollum contrived his James Bond Villain-style plan to obtain the Ring by letting Shelob eat Frodo and then combing through her fæcal matter rather than, say, pushing Sam and Frodo off the steep cliff and then climbing back down to take it from Frodo's lifeless body.
Seventh, I want a palantír bowling ball. That was even cooler than The Bowler's ball in Mystery Men.
Eighth, the physics of molten rock are different in Middle Earth. In the real world, if you're surrounded that closely by lava, you'll die pretty quickly of asphyxiation from breathing superheated noxious gases. Especially if you're in a mostly closed volcanic cavern like that. Not to mention that your hair and eyebrows will quickly burn away.
Ninth, Dwarves are comic relief. Gimli was my favorite character in the books; it was sad to see him reduced to such a rôle.
Tenth, Hobbits are gay. Not that there's anything wrong with that, but holy crap, I thought Frodo was gonna start kissing Sam on the mouth there at the end. And they all cry at the drop of the hat; the movie spilled more tears than blood.
Now, don't get me wrong, I liked the movie. And I'm rarely bowled over by special effects anymore, but Gandalf's ride up Mínas Tírith was just flabbergasting in its awesomeness. And though I have no problem with spiders (unless they've got a red hourglass on their abdomens and they're sitting in the recycling bin that I've got to take to the curb), that bit where Shelob appeared over Frodo totally creeped me out.