The champ:
1. Iron Man - Easily the most well rounded of the bunch. It has enough wit and entertainment value to spare, as well as a solid character arc to boot.
The meh:
2. X-Men: First Class - Has the strongest character development of the bunch. Had they stuck to the original plan of doing a Magneto (Testament style) origins story, it could have been something special. Instead it was watered down in an attempt to be more of an accessible popcorn flick to reach a wider audience.
3. Iron Man 2 - Focused far too much on the motto "bigger is better", without improving upon any one aspect. The banter wasn't as fresh the second time around, the final battle was somehow even more anti-climatic than in the first movie, and The Avengers Initiative subplot made it bloated.
4. The Amazing Spider-Man - Was far too self conscious and folded under the great responsibility of having to retread pivotal origin plot points. Although it was slightly more even overall compared to its predecessors.
5. The Avengers - Incredibly flawed for many reasons that I've stated before. At best, it functions merely as a passable popcorn flick to zone out to.
6. Spider-Man 1-3 - Goes back and forth from bland to being far too slapstick for their own good.
7. X-Men 1-3 - Had the potential to be Marvel's crowning jewel considering the source material is just that. Instead the potential was squandered much like with FC, as they didn't have the guts to fully delve into the social commentary that's the essence of the X-Men. It's truly unfortunate that the franchise never lived up to the compelling opening scene of the first movie.
8. Captain America: The First Avenger - Has an outdated, but well intentioned feel. It fits the character.
9. The Incredible Hulk - There's never been a strong indication that Hulk could hold down his own movie, but alas, it could have been worse.
The terrible (from bad to worse):
-1. Thor - Proof that Thor isn't mighty enough for his own movie. It's all so goofy.
-2. Punisher (04) - Frank Castle has never been the strongest of characters conceived and this movie does nothing to dispel that notion.
-3. Daredevil - Insipid & completely miscast.
-4. Blade 1-3 - The first two did not age well to say the least. Then Trinity came along with the final nail in the coffin.
-5. Hulk (03) - Ang Lee's identity crisis movie. You can tell part of him desperately wants the acceptance of the art house crowd, which doesn't jive well with a giant gamma irradiated poodle monster.
-6. X-Men Origins: Wolverine - It's apparent that no one involved really knew or cared about the source material. Heck, seems like they didn't care about making a decent movie for that matter...
-7. Ghost Rider - Nic Cage as Johnny Blaze is perhaps the most nonsensical casting call of all time. The rest of the movie is equally as absurd.
-8. Fantastic Four 1 & 2 - Both have that cheesy made for TV movie feel written all over.
-9. Punisher: War Zone - Felt like torture. Fittingly enough they used the tacky filters that Saw popularized. Reeks of Lionsgate out of every orifice.
Haven't seen & don't care to: Electra & Ghost Rider: Spirit of Vengeance.