Game Boy J

 These first 3 are from various J. League Soccer games.  I don't which exactly because I've already deleted them and because of the period they were all in the same folder just marked "J".

Jack Nicklaus Golf

"Dance Mode" in Jagainu-kun

Jagainu means Potato Dog.  It's a pun. I'm sure the other characters are similar puns.

Janosch

Jantaku Boy (the first of many Mahjong games)

Jeep Jamboree

Unplayable as every racing game on the system.

Jeff Gordon XS Racing

Jeopardy

Jeopardy:Teen Tournament Edition

Jeremy McGrath Supercross 2000

Jet De Go!

The Jetsons

Jidai Igeki

Jimmy Connor's Tennis

Jordan Vs. Bird (dammit)

Why do they even let me?  Why is it even something I can do?

Joryuu Janshi ni Chousen GB

Don't worry it is Mahjong.

Judge Dredd

All new 3D rendered scenes from the Jungle Book compressed and put on a GBC.

Looks good though.

That looks familiar.

You can't be...

It is (awful.)

Jurassic Park

Jurassic Park 2 Chaos Continues

Jurassic Park 3 Unlicensed

Jurassic Park 3 Unlicensed