This is my list of how I rank all of the Marvel movies I've seen so far (still a few to go). Captain America: The Winter Soldier and down are just there until they actually come out, so nothing past #22 is really part of the list yet. It's pretty hard for me to rank some of these, as they're so close in quality (mostly the good kind), but here you go! Feel free to make your own version of this list and share it with me; interested to see what other people's lists would look like.
http://www.ranker.com/list/my-marvel-movies-list/taran600,
Spider-Man 2
Best of the original Spidey trilogy.
Spider-Man 3
A very underrated movie in my opinion; I actually liked it more than the first Spider-Man, and almost as much as the second. There is so much emotion in this movie, and some awesome fight scenes with the Sandman and New Goblin. If you can get past a few "plot-holes" (which can actually be explained), Venom/Eddie Brock not being as best he could, and the dancing scenes (which were meant to be more funny moments, not so serious), it's a really great movie. Many people say that it was bad just because the dancing scene was supposed to be the only example of how the symbiote affected him. Wrong. While it was supposed to show that he was getting cocky and egotistic, (which admittedly it was a pretty poor job), there were other major examples of the symbiote effecting him. #1 He (thought) he KILLED Sandman, and wanted to while wearing the black costume. This is because it influenced his revenge/rage. #2 He was obviously stronger and more agile on the screen while wearing it. #3 While in the bar (one of the only bad scenes, which ends actually impact-ful when) he hits MJ. Peter would never have done any of these things without the influence of the symbiote controlling him.
While it had it faults, I still think it was a great movie (not to mention the phenomenal, and moving soundtrack). I so wish Spider-Man 4 hadn't been cancelled... I'm sure it wouldn't have proven the doubters wrong.
Spider-Man
Just about tied with the third Spider-Man film in my opinion, but still a great movie nonetheless. I haven't watched this one in several years though, so I may bump it up above Spider-Man 3 when I see it again.
For people who didn't like Green Goblin's costume/mask, go search for the "unused Green Goblin mask from the first Spider-Man film" on youtube. Unfortunately it wasn't used... "too scary" for kids supposedly, but it would have been awesome!
X2
X-Men
Thor
The Avengers
Easily (okay, not really) the best Marvel film ever! In actuality, most of the movies are very close for me, but this is still the top of the crop.
Captain America: The First Avenger
Best solo MCU character film thus far. Chris Evans is great as Cap, and I can't wait for the next one!
The Wolverine
Thor: The Dark World