Aliens vs. Predator (3 players) - Wiki
Captain America and the Avengers (4 players) - Wiki
Dungeons & Dragons: Tower of Doom (4 players) - Wiki
Dungeons & Dragons: Shadow over Mystara (4 players) - Wiki
Gauntlet (4 players) - Wiki
Ironman Ivan Stewart's Super Off-Road (3 players) - Wiki
NBA Jam (4 players) - Wiki
The Simpsons (4 players) - Wiki
Spider-Man: The Video Game (4 players) - Wiki
Teenage Mutant Ninja Turtles (4 players) - Wiki
Teenage Mutant Ninja Turtles: Turtles in Time (4 players) - Wiki
WWF WrestleFest (4 players) - Wiki
X-Men (4 players) - Wiki
A few of these are also available on Steam (D&D and Gauntlet was recently released). If you do go for the D&D games, I'd highly recommend you start with Tower of Doom. The learning curve is more forgiving.
While you didn't explicitly ask for it, some solid 2 player games that are in my favorites list are:
Fatal Fury series
Marvel Super Heroes
Marvel Super Heroes Vs. Street Fighter
Marvel vs. Capcom
Metal Slug series
Puzzle Bobble series
Real Bout Fatal Fury series
Samurai Showdown series
Shock Troopers (1 and 2)
Most of the 2 player games are fighting games but a few like The Punisher, Metal Slug and Shock Troopers can be played in co-op. Enjoy!!!
So far behind. Last night I was just playing GTA 5 despite beating it just to see how it compared to GTA Vice City. GTA 5 is the best. I was going to try GTA online too. That's always been the dream for nearly 20 years, an online GTA.I sure waited way too late to get into it, as I'm 1 year behind.
Other games I still need to work on: Assassin's Creed: Black Flag, Farcry 3, Jaurez gungslinger whatever game, I was doing some Skyrim addons. Game is still super boring. Not a fan but I've put 100s into it. It's the first one I haven't really liked. I like Fallout so much better.