There's no words to describe how amazing is this game.
It has the best gameplay, the N64 version is more responsive, but PS version has more characters and it's more stable, the choice is yours, if you have the legal copy of both, you can have it on your emulator.
This is the last perfect Mortal Kombat release (MK X wasn't released until this review), it has unique kombos for unique players, unique moves, I know that Scorpion has almost the same moveset as Human Smoke, but even them have their differences, Human Smoke has an uppercut kombo and Scorpion have teleport punch for both directions, also the kick kombo is different (Finish moves are also totally different).
There's countless possibilities in this game, the best fighting game ever.
I play it since 1997 when I got my Sega Saturn, played in PS, in PC, in N64, this is the real masterpiece in games.