Before connecting your phone to the computer through Samsung Kies, make sure that it has been properly installed because it seems that your phone is not discoverable due to a connection problem. When you install Kies you have the possibility to choose if you want to install generic drivers or not. If that option is unchecked then the computer will not be able to install the drivers for your phone. Samsung Kies offers a troubleshooting solution in case you experience connection problems. From its main interface click on the Troubleshoot connection error button and wait for the software to reinstall its drivers.
When you connect the phone to your computer pull down notifications from phone and click on USB Development and uncheck Android development and your phone will be recognized by the software where you can perform firmware upgrade, import/export operations and back up/restore as well.