I'm also counting adaptations.
Best:
Christopher Nolan's Batman Movies
King Kong 2005
The Thing 1982
Star Trek: While I don't think I've ever seen the orginals, I just love this movie.
Charlie and the Chocolate Factory
Godzilla Vs. Mothra (Heisei)
Godzilla Vs. King Ghidorah (Heisei)
Godzilla Vs. Mecha-Godzilla II: Ignore the II, this is a remake.
Godzilla Against Mecha-Godzilla
The Lord of the Rings Trilogy
The Harry Potter Movies
Dracula (Nosferatu, the Universal films, and the Hammer films.)
Frankenstein (The Universal films and the Hammer films.)
The Mummy Trilogy
Godzilla: Final Wars (Essentially a remake of Destroy All Monsters.)
Neutral:
Halloween: Excellent casting, but a little heavy on the sex.
A Nightmare on Elm Street: Jackie Earle Haley was excellent, but the rest of the movie kind of felt like a generic slasher. Thankfully there wasn't any nudity or sex, avoiding one of the most annoying cliches. However, the jump-scares weren't scary and were just flat-out annoying.
Planet of the Apes: I don't think I've seen the orginal or its sequels, so I don't know how it compares. However, with this movie on its own, I liked it.
Michael Bay's Transformers: I liked the effects, the new designs for the Transformers, I liked SOME of the human scenes, most of the actors ranged from decent to good, I liked the action scenes, the voice acting was great, and I liked the story. With that said though, the character development for the Transformers ranged from mediocre to poor, same goes for the humans, Megan Fox's acting was mediocre at best, The Fallen, Devastator, Shockwave, and Soundwave died too fast, and Megatron died.........TWICE!! ! Also, it pisses me off that modern-day technology killed off the Transformers, in the comics and the cartoons, even futuristic human technology failed to even scratch these guys. Only special humans forces such as the G.I. Joes and Cobra can stand up to them.
Godzilla: I liked the movie on its own, but it really had nothing to do with Godzilla. Now Godzilla: The Series, was more faithful to the Japanese movies.
King Kong (1977, I think that was the date.): The movie was okay, nothing much more to say.
Worst:
Friday the 13th: I know that in past Friday the 13th movies there was nudity and sex, but it never went overboard. This film on the other hand, felt like a porno with Jason Voorhees as a guest star.
Dragonball Evolution: Read/watch the manga, anime, animated movies, specials, etc. and compare it to the movies.......enough said.
The Last Airbender: Now while I haven't seen the show that much, have never seen the Legend of Korra, and have yet to see this movie, this movie just looks horrible.
The Twilight Saga Movies: The books look sh****, the films look sh****, enough said.