I've enjoyed the Angry Video Game Nerd's work since his Back to the Future review. Ironically, it's not really the infuriated rants by the Nerd that I enjoy (though the one at the end of Teenage Mutant Ninja Turtles was rather amusing because I didn't actually see it coming). Rather, it's the hilariously bad aspects of the games that are such anachronisms today that really make the videos funny. Stuff like Roger Rabbit's insanely long passwords or the stairway scene in Ghostbusters; terrible game designs that you don't see so much anymore. The actual Nerd persona, in my eyes, really just serves as a method of delivering the real humour in the games themselves.
I don't like all of his videos, though; it's definitely up and down with him. His first two videos (Castlevania 2 and Dr. Jekyll) aren't really that funny. But Castlevania 2 makes some very valid points and, except for the gratuitious cursing, actually serves as a decent enough "serious" review of the game. Jekyll spends too much time hyping up how bad the game is. Having played it myself, there are amusing aspects of the game not mentioned by the Nerd that would have been brought up had the actual gameplay footage been longer. (Like how the second level has birds that fly around and literally drop crap on you)
Roger Rabbit reminds me of his Castlevania 2 review: not terribly funny, but brings up good points. However, I rank Roger Rabbit below Castlevania 2, though, because Roger Rabbit is a game nobody would expect to be good, unlike Castlevania.
TMNT and Back to the Future are the high points, I think. They featured prominently the over-the-top fury of the Nerd while still mixing in valid points and humorous observations about the games ("you can just walk over it?").
McKids, Wally Bear, Master Chu, and Double Dragon 3 felt very...forced. The Nerd sounded very bored with the proceedings and the games themselves weren't very ripe for humour, except for "Bimmy and Jimmy". Top Gun had some absolutely classic scenes: the attempt to land the plane and the Nerd destroying the TV with a well-placed Hadouken and Sonic Boom.
The Friday the 13th and Nightmare episodes were very elaborate...maybe too much so. I actually liked the Nerd's struggles with the movie monsters, though the part with Freddy Kreuger attacking the Nerd clones was a bit over-the-top and the Nerd clearly lost focus while making it. However, the movies after that have been consistently good; I particularly liked the "guest star" of Spider-Man in that episode.