Best:

Dragon Quest IX: Sentinels of the Starry Skies (DS)
Kirby Superstar Ultra (DS)
Dragon Quest V: Hand of the Heavenly Bride (DS)
Castlevania: Portrait of Ruin (DS)
Castlevania: Aria of Sorrow (GBA)
Final Fantasy IV (DS)
Azure Dreams (GBC)
Jungle Book (GBC)
Pokemon SoulSilver/HeartGold (DS)
Pokemon X/Y (3DS)
Tales of Phantasia (GBA)
Legend of Zelda: A Link Between Worlds (3DS)
Golden Sun + Golden Sun: Lost Age (GBA)
Dissidia Duodecim (PSP)
KH: Birth By Sleep (PSP)

Worst:

Lufia Curse of the Sinistrals (DS)
Castlevania: Harmony of Dissonance (GBA)
Final Fantasy Adventure (GB)
Starfox 3D (3DS)
The Third Birthday (PSP)
Every game of the Virtual Boy
Metal Gear: Ghost Babel (GBC)
Resident Evil Gaiden (GBC)

Hold on there, the Virtual Boy had some good games. Wario is a great platformer, and teleroboxer is a more technical Punch-Out.

Best: Pokemon: Heart Gold

Worst: Super Mario 4. It's a crappy Japanese game I bought in Spain when I was 8 because I'm a moron.

Couldn't play the games more than 20 minutes at a time, so they quickly become disinteresting to me. There might have been some gems in the system, but my experience with it was so bad, I couldn't like any game that I played on it.

Best - Pokemon Red/Blue (Gameboy)


Worst - Water World (Virtual Boy)

Fair enough. I haven't had any issues with the VB, unless my eyes are tired, but then any screen will give me a headache then :S

Bear in mind that I was about 10 when I played them, so that impact left me with a negative view of the system and it's games. Probably if I'd gave them a chance nowadays I could manage to actually play them for a longer timeframe and get a more proper impression. Sadly getting a Virtual Boy in my country is impossible and online the system alone costs up to 200€.