Before I begin just listing them off, a quick reminder. These are OPINIONS. Don't waste your time trying to say I'm wrong because I'm not saying anything as fact. If you want to post yours here, I suppose that is also fine, as long as you aren't trying to cause a ruckus with a s***storm. With that out of the way...

Video Games

1. Goldeneye 007 is (I hate to say it, but it's deserved) severely overrated. It has a myriad of issues that are acknowledged...
2. Legend of Zelda: Ocarina of Time was not a masterpiece. It was a pretty good game, but it has... issues.
3. Medal of Honor: Warfighter is the best Medal of Honor game ever released.
4. Grand Theft Auto games are boring. Severely so in fact.
5. One of my favorite games of all time just happens to be a licensed game, not telling which.
6. Paladins is quite a bit better than Overwatch, and more balanced as of the moment. 
7. Super Mario Bros. 3 does not deserve most of the praise it gets. I have a huge problem with the mechanics.
8. Super Mario Bros. 2 is, quite easily, my favorite 2D Mario platformer.
9. Nintendo 64, as a console, had poor design and didn't do much to leap ahead of the SNES.
10. Cynthia was not that hard of a Pokémon Champion in Diamond and Pearl. You have to have a diverse team, but other than that... 
11. Generation 2 was, easily, my least favorite Pokémon generation. Difficulty curve problems, the worst balancing ever...
12. Aside from Whitney, the hardest gym leader for me was Wattson in Gen 3.
13. I don't like Elder Scrolls as a franchise. Half of the time it feels like the game is cheating you.
14. Fallout 3, as a game, is pretty mediocre. It feels really, really incomplete.
15. Fallout 4 is actually designed just right. Not too shooter oriented to be honest.
16. Final Fantasy VII: Dirge of Cerberus was better than the original game.
17. The original Borderlands was better than Borderlands 2 in almost every respect.
18. The Wii U was a better console than the original Wii, and had a better library of exclusives.

Movies

1. Marvel movies in general are severely overrated. They're no better than DC movies. If anything, they're worse.
2. I. Hate. Disney. They ruined Pixar, they're ruining Star Wars... I bet the list doesn't and won't end there.
3. Frozen was pretty meh honestly. People singing "Let It Go" off-key soon after it came out still haunts me...
4. I didn't like Despicable Me. I found the movie, how should I put it, a brain-rotting experience.
5. Phantom Menace was not that bad. It wasn't good, but it surely wasn't that bad...
6. Dark Knight Rises is just as solid as the rest of the Dark Knight trilogy.  
7. Not everything with Adam Sandler remotely involved is terrible.
8. "Grown Ups" is actually a really funny comedy, with some jokes still hitting even after watching it several times.

TV Shows (Including plenty of MLP)

1. Scootaloo is one of the least likeable ponies in MLP.
2. Rarity was at fault for the conflict in "Honest Apple."
3. "Somepony to Watch Over Me" is one of the best MLP episodes ever aired.
4. "The Washouts" was a TERRIBLE episode for RD, who I frankly think was less mature than Scoots there. I also don't see this "growth" I've heard as justification. 
5. I have yet to see a bad DC Universe show, even if the movies are bad. Even Arrow was really good, and Legends of Tomorrow was 9+/10 before they killed off Snark.
6. Deep Space Nine is easily the worst Star Trek series. Nobody was likeable whatsoever.
7. Star Trek: Enterprise is underrated. Sure it had a bad end to its run, but so did TOS.
8. Will Shatner should never have played Kirk. Chris Pines' Kirk is much, much better.
9. Captain Janeway is the worst Star Trek captain ever. Even over Captain Decker that was written to be a terrible captain.
10. Phineas and Ferb as a show is a disgusting pile of trash, aside from the platypus. He's fine.
11. Big Bang Theory is a heaping pile of garbage filled with offensive lowbrow jokes that are unfunny.
12. The new Magnum P.I. is miles better than the original series.
13. Star VS the Forces of Evil isn't a bad show yet (it used to be really good), but it's definitely sinking fast with the increased Starco focus...
14. The Walking Dead lost its luster after around season 1. All the drama ruined the show. 
15. TV has gotten progressively worse over the past 3 or 4 years.
16. Bull is actually better than Law and Order: SVU.

That may not be it, though. Expect to see edits in the future.