As Mirage said, the only thing you'd need to play an NTSC game on a PAL TV is a special cable which will convert the signal.
When you get asked if you want to use 50 or 60Hz, that's the game itself asking you; everything goes black and white with the 60Hz, so you most likely will need the cable. Unless you have another TV which you can play it on.

Still, an emulator is free and you don't need to buy any extra stuff.