How to Uninstall Windows 8 From a Dual-Booting PC

If you set up your PC to dual boot between Windows 7 and Windows 8, but have decided to end the experiment and go back to using Windows 7 full time, we have good news. It’s incredibly easy to erase Windows 8 from your hard drive and reclaim those precious gigabytes of storage space. 
Note: If you overwrote Windows 7 with Windows 8 rather than dual-booting, then you’ll need to do a full system restore from a back up.
To erase your Windows 8 installation from the dual-boot configuration and just have Windows 7, perform these steps:

• Boot into Windows 7
• Launch Msconfig by hitting Windows + R to get the run box, typing msconfig and clicking Ok.
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• Select the Boot tab.
• Select Windows 8 and click Delete.
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• Click OK to exit msconfig.
• Launch Disk management by typing “Create and format” into the Start Menu and clicking on the “Create and Format Hard Disk Partitions” shortcut.

Right click on the Windows 8 partition and Select Delete Volume.