Scratch

Well, im gonna tell you. But before you do this, you must go buy it (or you must have it and bought it) to do this cause it will be illeagal if you havent.

1. Go to emulator-zone.com
2. on the left hand side of the site you will see links. clikc the one that says nintendo64.
3. scroll down until you see a thing that says emulators. click Project 64 and download it.
4. then to get the rom. now, go to dopperoms.com.
5. In the search box type in The legend of zelda ocarina of time
6. scroll down and pick the rom that says ocarina of time.
7. then click the button that says download.
8. once youve done that, open up project64. go to file and pick out that rom.
9. now you can play ocarina of time on your computer for free!

any questions just ask.

PS you can also do this same thing, but with different n64 games. just get different roms.