Books - good story, horribly written. Clunky, piss-awful prose (though granted, there was the occasional nice turn of phrase), and wtf was Tolkien trying to achieve anyway? "England has no native myths of its own, therefore I will create one." Um, that's not how it works, chum. You can't consciously create a myth.
Anyway, the films, while horribly overlong, were at least nicely shot. And Jackson added some emotional depth to the characters that simply wasn't there in Tolkien's book, because he didn't think that sort of thing was important. Classic example of his near-autistic focus on plot over the internal landscape of the characters. It's telling that Tolkien didn't really give a toss about the story, though; he was far more interested in his endless fictional history and languages. It's the sort of thing that a 15-year-old boy would do, ffs. Anyway, the best scene in the film was entirely Jackson's invention - Gollum's conversation with himself (which he didn't actually direct; IIRC it was his wife on set that day). And Christ, but the last film went on a bit, didn't it?
In conclusion: Fuck Tolkien. Except for The Hobbit, that was good.