Japanese ROM: RPGC cannot host ROM files. However, the Japanese ROM can be obtained easily by doing a google search for Dragon Ball Z Ressen Jinzou Ningen ROM download, or something of that nature. Please do not e-mail the shrine maintainer requesting the ROM.
ROM Translation: Our very own RedComet has headed an excellent translation for this game, which can be found here: Twilight Translations: DBZ 3 English Translation
Emulator: Plenty of emulators are available to run this game, though I recommend FCE Ultra, as it's the one best compatible with the English translation.