The following list will guide you through how to play NES, SNES, Nintendo 64, Nintendo GameCube/Wii, Nintendo Gameboy/Color/Advanced, Nintendo DS AND Nintendo Virtual Boy games on your Windows PC.
There are many NES emulators, but Nestopia is my favorite. It is open source and is still being worked on. It plays all the games I’ve tried, it works with my gamepad, and has some advanced options. It even supports multiplayer over the Internet! Download Nestopia here.
ZSNES is a great emulator, the interface is weird, but it works great. A tip I wish I knew a long time ago is that when you have you mouse in the window, you can hold the right mouse button to move the window. You can read a great tutorial about ZSNES here and download the program here.
Project64 has been working on their 64 emulator for a very long time. You can get the beta (1.7) if you donate, but the stable 1.6 is free and great. The only problem I have with Nintendo 64 emulation is that it’s hard to emulate an N64 controller, but that isn’t Project64’s problem. You can download it here.
Dolphin is the only emulator I know of for GameCube or Wii games. I was surprised to find that Super Smash Brothers Melee was going at a playable speed. Dolphin is updated weekly and seems to be progressing well. It comes in both 32 bit and 64 bit applications, which you can download here.
All of these emulators are rolled into one package with Visual Boy Advance. It has not been updated since 2005, but it works great. One nice feature is that it can play roms that are still in a zip folder. So there is no need to unzip. Something you may want to look out for is Visual Boy Advance-M, which plans to improve upon VBA. For now, you can download VBA from here.
Nintendo Virtual Boy
Oh come on. Why would you want to do that to yourself? Red Dragon is probably the best we’re gonna get. There is little to no interest in emulating this failure. Download it here, if you must.