The best in my opinion is the Joker from The Dark Knight (2008). That film emphasizes him as the antithesis to Batman, moreso than any of his previous incarnations. It also manages to create a unique, fascinating version of the character .... This is a Joker unlike any we've ever seen before, but it's still true to the character .... It doesn't diminish the character with an origin story (in the Joker's case, an origin story does kind of diminish the character because "mysterious" is as much a part of the Joker as his craziness). For all we know, there was no failed comedian or Red Hood or chemical vat - there's just this "Joker"; he has no reason for being and no reason for spreading chaos. This Joker fits perfectly in Nolan's universe .... It's scary, ugly, remorseless, pure evil .... and we love it. We love to see him stick pencils in people's heads. We love to see him carve smiles in people's faces. We love to see him light people on fire, and feed people to their attack-dogs. We love to see him hurt and kill and plan and spread chaos. Because he's the Joker.
The Green Goblin was decent, but the best villain in the Spider-Man movie series in my opinion is Doctor Octopus. It's practically him jumping off the comic page and onto the big screen. Perfect actor for the role, exactly how I imagine Doc Ock in the comics. And the arm special effects were ****ing superb. Spider-Man 2 (2004) is probably my second favorite comic book film, after TDK, and Doc Ock is one of the reasons why (don't misunderstand me, he's not one of the most important reasons .... the second movie is probably the closest thing the filmmakers are going to come to when it comes to making a perfect Spidey movie, and a lot of it was the Peter and Aunt May portion, the way they handled the Peter-MJ relationship at that point in the series, the parts with Peter "losing" his powers and contemplating giving up his life as Spider-Man [but changing his mind and donning the costume again when he sees that boy's faith in Spidey], and the train sequence). But yeah, Ock was tight.
Magneto was done well. Shakespearean actor, anti-hero, sympathetic backstory, decent costume, plastic prison. The films do a decent job of translating Mags and Charles' relationship onto the big screen, and stressing the differences in their ideals (which ultimately led them apart) .... Magneto is the Malcolm X to Charles Xavier's Martin Luther King JR. I think Stryker was cool too, him and his attack-dog Deathstrike were badass. The whole military side was a cool part of the character, even though he was just a reverend in the comics.
The worst villains .... well, Galactus in Fantastic Four 2: Rise of the Silver Surfer (2007) was pretty ****ty. In fact, that whole movie series is one big turd, and I wouldn't doubt that the unreleased, low-budget '90s FF movie is better than both the new versions combined. How you gonna make Galactus into a damn cloud?! A gigantic dude wearing a ridiculously-tall purple helmet would be less retarded than this.
Red Skull. From the 1990 Captain America movie. Everything about that movie sucked ***. Red Skull was an Italian Fascist officer named Tadzio de Santis who, as a child in 1936, was kidnapped by Italian army stormtroopers and subjected to experiments led by Nazi scientists attempting to create an ubermensch. The United States replicate the serum and test it on a polio-stricken adult man - thus, Captain America is born. The Skull plans to launch a missile at the White House, and Cap is sent to deactivate it. Cap is defeated and gets tied to the missile. As he grabs ahold of the Skull, the Skull is forced to cut off his own hand in order to avoid being launched into destruction with his "American brother." In DC, a young boy named Thomas Kimball (essentially Bucky) takes a photograph of Cap and the missile as they fly overhead. Cap forces the missile to change course and land somewhere in Alaska, where he remains frozen until 1993. Kimball goes on to become a Vietnam hero and, eventually, the POTUS. The Skull is alive and has had extensive plastic surgery and a daughter. He is the leader of a powerful crime family, and it turns out that he was involved in the murders of MLK, JFK, RFK. Now the Skull is targeting Kimball for assassination. Cap is found in Alaska and thawed out by researchers, blah-blah-blah. You get the picture. This guy's a douche.
Bruce's daddy, David ("Absorbing Dad"), from Hulk (2003). There are so many things wrong here. He gets put into a mental hospital after conducting dangerous experiments to cure his son Bruce, who has inherited David's mutated genes. David killed his wife after his research was shut down. Years later, he spies on Bruce (who now has the adopted last name "Krenzler"....WTF) as a janitor at the facility where he works. He uses Bruce's DNA to make Hulk-dogs (the Hulk-dogs were actually in the comics) and eventually subjects himself to radiation, gaining the ability to absorb the properties of any object he touches. But David wants Bruce's power, and by the end of the film, when he has bitten into an electrical wire and gained its conductive properties, he tries to absorb Bruce's Hulk powers.