You cannot emulate Galaxy (or any other phone for that matter). If you need it for app development purposes, use the emulator shipped with the SDK. That emulator doesn't emulate any physical device. It just emulates Android platform on your computer to ease up the development process. This consequently means that there is no guarantee your app will work correctly on any particular device if it's working correctly on the emulator, so you still need to test it on a actual device.
