Just a heads up for everyone...
The karaoke scene is no more than a few minutes long if you're having trouble, the scene where you have to press nothing for a hour is only an option you can pick to complete the scene while doing it in five minutes is also an option, and I can't find a place where 10-20k punches are necessary.
There are videos on Youtube of the game being beaten in under 30 minutes without using the warp glitch JRL mentioned. It's not too hard in the least, only unconventional and unorthodox in the things it requires you to do, such as getting divorced. If you want a hard game, go play Holy Diver.
Why am necrobumping this? Because I'm taking a break from Metroid 2 for a while and am working on a warped run of this game and may do a warpless run some time later. I'm having some trouble with the karakoe sequence (the only sequence required to complete the game; failing to do this results in a game over once you reach the treasure) even though there are supposedly some workarounds for the microphone. You have to get the audience to approve of your singing of a short verse three times, but I can only get them to randomly approve once, and often its by not doing anything at all. I don't get it.
Do we have any Japanese gamers who are familiar with this game? I'd like some tips as to how the heck to complete this sequence.
A hundred years from now, they will gaze upon my work and marvel at my skills but never know my name. And that will be good enough for me.