You thought VDT had a better story?! Do you mean as an adaptation or just as a film? Or are you talking about the books?
I think most people will agree that LWW worked the best as a standalone film and as an adaptation.
PC was an interesting mixture. Some parts were really, really good. All of the stuff about the Golden Age of Narnia being gone were very beautiful and poignant for me. And Reepicheep was awesome!! Eddie Izzard was the perfect actor to portray Reep and his dialogue, animation etc. was near perfect (and, as you can probably guess, this is pretty important to me). They got a lot of the themes right and in some ways I liked it better than LWW... however, some parts drove me crazy as a fan. Suspian didn't bother me that much honestly. It's so short and insubstantial, you can basically ignore it. Caspian getting in a shouting match/rivalry with Peter was just wrong. For Caspian, High King Peter coming back is like King Arthur coming back for us. In the book, Caspian is in total awe of Peter, and the other three Pevensies. Caspian's education with Dr. Cornelius was cut unfortunately. It's one of my favourite parts of the book and I was very sad to see it go, but I understand that there wasn't really a spot for it and they got the main idea of that scene (the sadness of the Golden Age being over) in other scenes. What I couldn't understand however, was the cutting of the romp at the end (Aslan turning boys into pigs, an abusive father into a tree etc.)! I understand it would be a complete change in tone from the rest of the movie, but that's kind of the point. After centuries of magic being suppressed by the Telmarines, it's back in full force. They needed to cut out most of the Second Battle of Beruna (the last third is too action heavy) and put the romp in its place. So overall, as an adaptation, it was mixed, but certainly more good than bad. What they got right, they really got right. There were lots of moments (probably more than LWW actually) that gave me pure fanboy delight). As a movie, I would place it slightly under LWW.
Then there's VDT. What a trainwreck. As a movie, I just thought it was really juvenile and forgettable, the sort of movie you watch once and forget about an hour later (unless it happens to be an adaptation of one of your favourite books!). As an adaptation it was just cringe-worthy. The good things were Will Poulter's performance as Eustace (he did for Eustace what Izzard did for Reep; wonderful casting) and the design of the Dawn Treader. The bad things are legion. The Green Mist was dumb, a mindless evil with no motivation or even any real threat (the Lone Islanders it "swallowed" were completely unharmed). The story goes from being a selfless quest of honour to recover seven lost lords to a desperate quest to find seven swords. Credit is taken away from Aslan and given to Eustace for the defeat of the Dark Island. The Undragoning (one of the most important scenes in the series) is intercut with a Sea Serpent battle and totally slopped up. Caspian's clever trick and the brilliant dialogue between Caspian and Governor Gumpas was replaced by a generic sword fight. The joke at Ramandu's Island ("If it is a distraction for you...") was inappropriate and totally killed the atmosphere of the scene. Lucy and Edmund both suffer character regressions, especially Edmund. Lucy acted more grown up in PC than VDT and much of Georgie Henley's acting came across as really awkward, clearly meant for someone half her age. Edmund was just butchered. I loved Edmund in PC. At the end of LWW (book), Edmund is described as growing into a grave and quiet man, great in judgment and I thought PC showed this really well. In VDT, Edmund is almost back to where he was in LWW (e.g. sticking his tongue out at Uncle Harold ). And then he gets tempted by the White Witch (who has no right to be in this movie)! Edmund is past this nonsense! He shattered the Witch in PC, mirroring the Witch stabbing him in LWW, bookending his arc. Story's done. I'm guessing reason behind both of these regressions was the film-makers wanting to remind the audience of the 740M earning LWW, since that seemed to be the thinking behind much of this movie. *headdesk*
Where sky and water meet,
Where the waves grow sweet,
Doubt not, Reepicheep,
To find all you seek,
There is the utter east.