If you wanna see some reviews of some horrible NES games, check out:
YouTube - JamesNintendoNerd's Channel
There are some hilarious videos there where the guy is cussing about the Fester's Quest game, TMNT, Dr. Jeckyl and Mr. Hyde comes to mind as well
As far as horrible games I've played, there was a game for SNES called "No Escape!" I believe. No save feature, no passcode, no warp code, and I don't even think theres a walkthrough of it on GameFAQs. Its that bad. The funny thing is it has a cool concept, it was based off a movie I think with that guy from Shawshank Redemption. You collect various items around an island and trade for others to make devices to escape with, as well as weapons I think. Tough game though, you get 3 lives I think and no continue.
I hate the game Trog for NES, although my buddy loves it, I don't know why, I think its horrible.
Mario Party, I despise Mario Party. It a game/series that has so much potential, it could be a great game, but it's the worst simply due to the way it can completely screw you over in the final turn of the game. You could have destroyed everyone in every mini-game across 20 turns, have a stock of coins and stars, and then in the final turn you or someone else lands on a chance square and they switch stars/coins with you, or they wipe you out and some putz wins the game instead. What horse shit, I refuse to play the damn thing anymore, more times than not I get screwed in the end. It becomes a game of luck and not skill, if I want to play a game of chance I'll go to Vegas.
DC vs. Mortal Kombat. They obviously were trying to compete with the Marvel vs. Capcom games and they failed miserably. A weak competition at best, I was lured by the commercials and the hype, shouldn't have bought into that. You have like...16 players you can pick from total, and you can't play with more than 1 character at a time. Lame. The overall mechanics aren't that great either, they obviously went for showy graphics rather than a fun factor.
Unfortunately its not easy for me to judge horrible games because it takes a lot for me to be let down normally, or a game has to be really horrible for me to quit wanting to play it all together.