You will need
  • A computer running the Windows operating system
Click on the icon "My computer" right-click in the resulting menu, select "Properties". Then click on the tab "advanced settings" in the window that appears, find "startup and recovery". Next to that line, click "Options". Now find the inscription "Operating system that is loaded by default. Below the inscription is the arrow. Click on it with the left mouse button. From the list of operating systems choose the one you will use. Just below is a row "to Display list of operating systems". In this line, uncheck it. Close all Windows.
Then restart the computer. Now when turning on PC Windows operating systems will not. When OS boots up, click the hard disk where there are unwanted operating systemand delete their files. Typically folders have the old OS called Windows.old or Windows.2. The junk files the operating system needs to be deleted as ordinary files and folders.
You can also format the partition on which you installed the operating system unnecessary. Of course, this should be done in case if one hard disk partition you don't have at the same time and working operating system. If the hard disk partition no working OS, then formatting will be the fastest and best option. Before formatting don't forget to temporarily move the desired files to a different hard disk partition.
If you will see the Temp folder, they also need to be removed because they store temporary files of the operating system. Deleting all folders with the same name, you free up space on your computer's hard drive.
Also find the files delete the operating system file called Pagefile and delete it. Is the paging file memory to the operating system. Since this OS is no longer working, he will not be required.