Hello Everyone! This brief tuto is going to teach you how to backup your “Windows Registry”

The Windows Registry is a  database that stores configuration settings and options on Microsoft Windows operating systems.This
 registry is editable. 
Before you edit the registry, export the keys in the registry that you plan to edit, or back up the whole registry. If a problem occurs, you can then follow the steps how-to restore the registry to its previous state.

How to Export Registry Keys

Click Start, and then click Run.
In the Open box, type regedit, and then click OK.
On the File menu, click Export.
In the Save in box, select the boxes at the bottom according to weather you want to export all or only selected branches of the registry.
Next select a location in which to save the backup .reg file. In the File name box, type a file name, and then click Save.
How to Restore the Registry
To restore registry keys that you exported, double-click the .reg file that you saved. 

Hope you got it.  :)

If you encounter any problem let me know  through a comment here.