Do note that most of these games are great classics.
The fourth stage in BTDD. I had to save state on the emulator and quick load the last moment of the fight against the Dark Queen's ship soooo many times... but it felt great to clap a childhood challenge (that stage plus the entire game). That was my reward. Never again, especially without save states.
Moonwalker. Yes, with Michael Jackson.
Star Wars Ep 1: Racer: the Abyss track was so hard. I couldn't beat it; my brother had to do it. My favorite racer was Neva Kee, but the only person that we could ever beat it with was Bullseye Navoir. Smooth turns kept you on the upper track. Nevermore.
Mortal Kombat 2 and Shaolin Monks. Beat it, and swore never to respect Shao Kahn for being such a coward. Again? Nope, fuck Shang Tsung, fuck Kintaro, and fuck Shao Kahn.
Managed to kill Carnage in Maximum Carnage. I had to get high to do it. Love the music, but I'll never mess with Carnage's bad ass anymore. Too much badass.
Never got every emblem in Sonic Adventure 1. Too disappointed with such a broken, chancy PoS of a Sonic game (1 minute, Sky Deck, Knuckles) . As for Sonic Adventure 2, which I liked, I can brag about my geometrically complicated mind and say that I clapped Rouge's Mad Space in minutes, all A-rank, but what in the fuck would I do that to myself for? Craziest shit since Trigonometry.
Motherfuck Sonic Heroes. Just fuck that assy game.
Rayman 2 was almost one of my favorite games until I saw the ending. That sapped it of replay value completely.
JGR and JSRF.
Starfox Adventures: friggin' tired of saving Slippy Toad's ass.
Spawn Armageddon.
MvC3. 2 was better.
Final Fight.
The final showdown in event mode on SSBM. I could beat it only with Samus.
All-Star on very hard in Melee; anything hard in multi-man melee, especially getting a lucky TKO in any SSB Cruel mode with every character.
SSBM again: getting that punching bag to fly with Craptain Falcon.
Duck Dodgers.
Yoshi's Cookie.
The level in SMW with the unsteady platforms in the sky that sink if you stand too long, plus the Ghost Ship. Oh, and the Special levels... The last time that I played those was at Taucer's house.
Left 4 Dead 2... yeah, I beat it easily but I can still hear that Witch...
Any Call of Doodoo or Gears of Bore.
Someone mentioned the annoying parts of Jet Force Gemini. Great game though.
Capcom vs SNK: last SNK challenge featured a complete asshole.
Power Stone 2. Love the extra characters but 1 was better.
Brawl.
Max Payne.
PoP: Sands of Time.
Contra. NO. PLEASE GOD, NO!
Honest to God, Mario 1 through 3. I'm serious, fuck if I'm skilled.
Super Mario Land, on one set of batteries. This was before I knew about emulation. Those gameboys were bricks.
Blast Corps for three seconds. That was hard. NEXT!
Kirby 64. Disgrace to Kirby.
Castlevania 64.
Bushido Blade series
Crash Bandicoot. Fuck him.
Halo.
DBZ Hyper Dimension.
DBZ Sagas. PoS.
The mini-game coaster in Mario Party 2. SO UNFAIR AND SO UNWORTHY WHEN YOU BEAT IT!
Turtles in Time. No more of that madness.
SoR3 would be worth it if the soundtrack didn't suck so bad.
I would play SM64 again, but all I get is a kiss, some cake, 100 lives, a glittery triple jump, and no classic jockey fun with Yoshi! You're an asshole, Yoshi, a complete asshole.
I could name more, but
FFFFUUUUUUUU!!!