This video simple tell you the way to save backup your SMS and contact before factory reset on your PC and then i will tell you how to restore it will these backup files:
1. open the messages on android phone & press the manu key and then select Import/export.
2. Choose location where you want to create backup.
3. Now open the contacts and Press the menu key and choose the export.
4. Choose the destination location.
5. Location where these backup files are stored on your SD Card