Step 1:

On the front page pick a platform eg, Microsoft or Nintendo.

Step 2:

Pick a console and click on one of the links (Make Sure it's ISO or Decrypted.)

Step 3:

download a game.

Step 4:

Go back to Sandler Site and click on the emulators drop down menu beside the playback window (the speaker and volume control)

Step 5:

Pick an emulator for whatever game you want to play.

Retro Arch has most emulators the other ones are for good measure.