You can try to delete the partition through Disk Management by referring to this article on Microsoft Support.
If this partition is bootable, it may not let you delete it. The best approach is to format the hard drive and re-install the operating system. You can refer to this link for OS re-installation: Installing and re-installing Windows 7
Note: If you perform a clean installation of Windows, any data on the computer will be lost. Please perform a data backup prior to this step.
Follow the steps on: To install Windows 7 using the Custom option and formatting the hard disk
Alternately, you can restore your computer to factory settings if you created any system image or if you have any recovery discs provided by the computer manufacturer.
Hope this helps.
Please reply if you have any further questions.
Thanks and Regards,
Hey all, I recently made a partition for the (forget the exact name) but the I guess demo version of Windows 8. I will just upgrade to Windows 8 when it comes out. Is there a way to get rid of that partition, and just have my hard drive back to the way it was? Steps would be very helpful, thanks a lot!