Starting with the Olivier release, there were a couple of interesting points. One thing I found interesting, from an historical perspective, was how short the credits are. Yes, typical for the time, but that was the first movie I watched where that really caught my notice. Compare the three or four screen-fuls of credits to the crawls on modern movies that go on long enough to play two complete songs. Also note that, IIRC (I haven't watched this version in a number of years), all of the credits were at the beginning.
Anyway, I mentioned a major story change. Very near the end of the story (chapter fifty-six of the book, out of sixty-one), lady Catherine de Bourgh drops in, unannounced, on the Bennets. Her goal was to talk to Elizabeth, and have confirmed that Elizabeth wasn't, and wouldn't be, engaged to Mr Darcy. In the original, Elizabeth affirmed the first, denied the second, and lady Catherine left in a huff, after heavily insulting Miss Bennet and family.
In this version, lady Catherine was amused, and affirmed that Miss Bennet would be a good match for Mr Darcy. I believe, in fact, that he was in the cart with lady Catherine, and proposed forthwith.
As I alluded, a pretty major change, but one that worked quite well, and made lady Catherine much more human. So I still rather like the change.
To keep in chronological order, another "version" of the story (sort of) was in Bridget Jones' Diary. Well, ok, this was a modern take, and the liberties taken are huge. Still, a very entertaining movie, if at times silly.
I can't say as much for the sequel. Thank goodness I saw this on DVD, rather than in the theater. The best part of it was the bonus feature that had Rene Zellweger, in character as Bridget Jones, interviewing Colin Firth (as Colin Firth). That was hilarious; the movie itself was pretty lame, unfortunately.
Next up was Chadha's modern Bollywood take, Bride & Prejudice. I generally enjoy Bollywood's extremely over-the-top style, and Aishwarya Rai is a nice addition to nearly any movie. And making it a musical is rarely a bad thing, IMHO. Lots of fun.
Wright's version, the year after, was a huge disappointment for me. I'm generally a fan of Keira Knightley (I thought she was great in Chadha's Bend It Like Beckham, and did as much as possible in Love, Actually and the Pirates of the Caribbean trilogy), but I can't for the life of me understand how she got an Oscar nomination for P&P.
Update: I found the rant to which I referred. It actually wasn't nearly as long as I remembered. And the complaint about the smirks was the only part that referred to Ms Knightley. The other things that bothered me were the near removal of the father (my favorite character), and the mother's character being vastly changed by two scenes (unfortunately, I didn't note what the incidents were, nor do I remember) to make her less annoying, as well as the inevitable compression of the story.
In fact, the only good thing I can remember about the movie was that the original of my favorite statue from the Louvre showed up in the background at Pemberley. That statue is Dirce: