VirtuaNES is a relatively new NES emulator from Japanese origin.
Fortunately there is an English version of it though.
Being newer than other NES emulators doesn't mean it's bad, on
the contrary in fact. It supports full CPU and sound emulation.
As with most emulators for Windows, VirtuaNES requires a recent
version of DirectX. Being a NES emulator it doesn't require a
very fast PC though.