Once you have installed a Samsung emulator it's a little bit difficult to understand how to use it. Here is a little guide to start a midlet in the emulator (from Samsung website).
"To run your MIDlet on the emulator, please place your JAD and JAR files in a folder which does not contain any special character or space in its name. Click "File", "Import MIDlet" and then locate where your JAD and JAR files are.
"To run your MIDlet on the emulator, please place your JAD and JAR files in a folder which does not contain any special character or space in its name. Click "File", "Import MIDlet" and then locate where your JAD and JAR files are.
If the phone skin is too large for your computer, placing the phone’s keypad out of view, please use num keys of your keyboard."
URL: developer.samsungmobile.com/Developer/resources/board_read.jsp