Gran Turismo, I have always loved the franchise since 3, but I don't feel I'm really good for what I play, I could be wrong... the other is Mario 64, the game was great for its time, but I never could used to it and actually I never finished it.

I love UMVC3 to bits and always play the arcade mode here and there but after playing online, I realised that I sucked even if I was able to beat arcade mode on v. hard without dying :(

I'm good at every video game!  Castlevania III is the bane of my NES existance, I'm also horribly bad at the Sonic Genesis games.

Megaman 2 at least wasn't that hard. And I suck at 2D platformers mostly, though there aren't a whole lot I 'love to pieces'. One that would fit that category and answers the OP's question would probably be Super Mario Bros. 3. Otherwise, outside this genre, probably a fighting game like SoulCalibur. I suck at fighting games in general, but I think SoulCalibur on Dreamcast is one of the best games ever made regardless.

Fifa online!

Super Smash Bros.

One day, I WILL be good at it! ONE DAY!!!! ... Not today, though.

I don't suck at any game, though I'm less awesome in Mirror's Edge than other games I like.  I still like it.

Tekken series.
Makes me scream but I love it so much.

I suck hard at fighting games but I love the classics like Street Fighter II, the original MKs and Killer Instinct. The one fighting game I was actually good at and could do most of the moves was the original Clayfighter.... Ickybod Clay FTW!

I wish I was better at Tekken.  I don't suck at it unless you compare my skills to the dedicated fanbase or pro players, then yeah, I do.