Personally I don't see the point in playing 3 and 4 in Japanese (even partial Japanese) when the games were originally created in English and released in English for computers for the English-speaking world.
You also have to remember that the games up to 3 are very unfair in that you can pretty much die at any time due to bad luck. And most of the game is just hundreds of hours of grinding (back in the day when grinding was a new concept). I would advise playing using an emulator and using savestates to prevent this. Or at least emulating the Apple version and copying your disk image, something you can't do on the console port but which people *had* to do on the Apple back when the games were new. Nobody wanted to grind for hundreds of hours, randomly die, and have to grind for hundreds of hours again.
#4 is notoriously unfair (literally notoriously--people talked about it at the time) because not only can you not gain levels normally, you pretty much have to read the mind of the developer to solve some of the puzzles (one enemy requires getting a specific monster to kill it that you would have no other reason to suspect would be useful). There's no way you're going to solve 4 with the messages in Japanese.
I ended up playing 1-3 on an Apple emulator, 4 not at all past the first few levels except by using a walkthrough, and 5 on the SNES. 5 has the typical Nintendo censorship (no alcohol for instance) but didn't lose anything aside from that, and has improved graphics. 6 and 7 existed for DOS (you probably need Dosbox by now) with 7 also ported to Windows. 8 is new enough that it's a regular Windows game.