Well from the games I can remember...
Best Games Moi has played in his lifetime:
-Punch Out!![Wii/NES]
Challenging, easy-to-play, comical and most of all a fun game. One of the few games I actually replay from time to time.
-Breath of Fire series (minus Dragon Quarter [PS2])[SNES/GBA, PS/PSP]
One of the firsts RPGs I played when I was kid, and one I'm quite fond of. Love all the characters in the series, both good and bad. Plus you can turn into a damn dragon! I loves me those dragons. Yes the gameplay was your basic JRPG, but I found this series to be some-what unique because of it's cast of characters, dragon transformation and I found all the games quite memorable (even DQ).
The reason why I'm not counting DQ isn't because of it's gameplay (in fact,
the gameplay was good), but the whole setting, only having 3 party members throughout the whole game, and the timer like dragon gauge (which really sucks cause the best thing about the BoF series is the dragon transformations, IMO) made me feel a bit uncomfortable calling this a BoF game.
-Gitaroo Man [PS2/PSP]
Best rythem game I've ever played. It's tough at first but once you get used to the gameplay mechanic you got quite an addicting and fun game on your hands. Like Punch Out!!, I find myself replaying this game from time to time.
Never played the PSP version so I can't say if that thing called an analog stick hinders/ruins the game.
-Super Mario Galaxy [Wii]
Playable 3D Luigi, 'nough said...plus the whole game was great too I guess.
-Mario & Luigi: Superstar Saga[GBA]
Yes, all Mario RPGs are fun, and most say that SMRPG is the best of them all. Personally, I like the Mario & Luigi RPGs the most, solely for its counter attack/dodge mechanic. The reason why I don't count the whole trilogy is because PiT's boss battles seem to have lasted for hours and BiS, though a great sequel, I found myself to be a bit...dissapointed on some of it's boss battles, boss designs and how the story progressed. Though it is very close to SS.
-Mega Man X [SNES/PS/PS2, GC]
The best of the whole series. One of the cool thingd about this game was how some of the stages changed if you beat a particular boss. Another thing I found cool was that one of the Light Capsules was protected by a well-armored sub-boss. I don't recall there being another capsule protected by a sub-boss in the later installments.
-Chrono Trigger [SNES/PS/DS]
The game soundtrack was and is still the best <insert name of composer here> has ever concived, the cast are just loveable, all the characters and mobs were designed by [that guy who draws the Dragon Ball manga and anime and Dragon Quest/Warrior games, someone tell me his name cause I'm to tired to look for his name at the moment], which is a big plus for me for some reason, had multiple endings and time travel.
Also, no random encounters.
I don't think I played any games which I truly find horrible or bad enough to be called The Worst Game I've played.
Or maybe I just don't want to/can't remember them.