How do I go back to previous operating system? Can I uninstall Win8 RP? Any suggestions?

If you made an Image of the previous installation as I state in Step 1 of my installation procedure then simply restoring that HD Image would do this in 10 minutes.

If you did not make an Image, then you would need to install the original OS from scratch using your installation media.

If your PC happens to have a Recovery Partition you can restore to factory OS using this Recovery Option.

We have posted warnings in many different threads about the fact that when you install Win 8 RP over another OS you will loose the original OS.This is a warning directly from the MS approved download site:

ISO images:
An ISO image must be converted into installation media stored on a DVD or a USB flash drive.
Instructions are provided on this page. Developer tools are available for download from Windows Dev Center.
Important: If you decide to go back to your previous operating system, you'll need to reinstall it from the recovery or installation media that came with your PC, which is typically DVD media.
If you don’t have recovery media, you might be able to create it from a recovery partition on your PC, using software provided by your PC manufacturer. Check the support section of your PC manufacturer’s website for more information.
After you install Windows 8, you won’t be able to use the recovery partition on your PC to go back to your previous version of Windows.

Hi Ted,
Really sorry for my late reply. Now I am using Windows 7 Pro and everything goes well. Your suggestion helped me a lot and thank you so much.

Glad I could help. Please let us know which process you used to recover Win 7. Others may learn from your experience.