2. Take backup of all your phone data on SD card, contacts, messages using Kies.
3. You need to at least charge your phone to 60%.
4. You also need to enable USB Debugging on your phone. This can be enabled by heading to Settings > Applications > Development > USB Debugging.
5. Close apps on your computer such as antivirus software, Samsung Kies PC Suite, and firewall software.
6. Download the root package from - http://adf.ly/AmlD5
7. Copy the downloaded ZIP file to your phone’s SD card root.
8, Switch off your phone. Then press home and power button together to go into recovery mode.
9. From here, choose “Install zip from SD Card” and “Choose Zip (“upd_1.zip”) from SD” using the Volume Up and Volume Down key and the press home button to select it.
10. Install will start and In 5-10 mins root process will finish. Once the rooting process is done, select reboot using volume up and down keys to reboot your phone.
11. Browse the apps in phone now and you will find "superuser" app. It proves rooting is done.
Same way to Unroot phone, download zip from here - http://adf.ly/AmlJM
and follow the steps from 7-10.