[quote name='Gameboy415']Not sure if you're open to imports, but since they're so easy to play on a GC with a Freeloader I HIGHLY recommend:
-PC Genjin (a remake of Bonk's Adventure!)
-Takahashi Meijin No Boukenjima (a remake of Adventure Island!)
-Nintendo Puzzle Collection (Dr. Mario, Yoshi's Cookie, and PANEL DE PON/TETRIS ATTACK!!!)
-Kururin Squash (fun maze game)
-Mr. Driller Drill Land (4-player Mr. Driller)
-Donkey Konga 1-3 (3rd one never came out in the US and 1 & 2 have a few different songs not in the US versions)
None of the games require much Japanese knowledge and they're all fun as hell![/QUOTE]
Kururin Squash is a must-buy. It's a weird game, it has a really fun 4-player multiplayer battle game and it is cheap. You can't go wrong with it. Not too hard to figure out, either.
I have to point out, though, that Donkey Konga 3, while in theory a great game, *DOES NOT SAVE PROPERLY* when using Freeloader, or even with at least some mod-chips (drive chips). In all cases you MUST use a separate memory card for your Japanese games and you MUST be careful not to get them mixed up as you are liable to accidentally erase one or the other if you do, as the games will ask you if you want to format them if you have them mixed up and if you can't read Japanese, you may accidentally choose to format the card!!!!
Even if you use a separate memory card for Donkey Konga 3, the game will still not save properly and so unlocks and such don't work, which is hugely disappointing. So in the case of DK3, I would say to only get that game if you have an actual Japanese Gamecube. Kururin Squash doesn't have this problem, though, so I definitely recommend that game - it saves fine. I haven't tried any of the others you mention. I'd like to know if you know if any of them have this problem.