If you want to install Windows 8.1 on this computer you will need the installation disc and a legal product code. You can download a ISO image of Windows 8 or 8.1 from here. You will need to burn the ISO file to a disc to create a bootable installation disc. You can do this using Imgburn, or if you are using a Windows 7 or Windows8/8.1.
Burning a ISO file to a CD or DVD with ImgBurn
To burn a ISO file to a CD or DVD with a computer with Windows Vista or earlier, please downlaod ImgBurn
and install it.
Insert blank CD or DVD into your CD/DVD drive.
Open ImgBurn, and click on Write image file to disc.
Click on the Browse for a file icon:
Locate the ISO file you want to burn, and click on the Open button.
Click on the blue arrow to start burning the bootable CD.
How to burn ISO image using Windows Burn Disk Image.
Notice: This applies only to Windows 7 and Windows 8, earlier versions do not have this.
1. Place a blank CD or DVD in the tray of your optical drive and close the tray.
2. After you have downloaded the ISO image you want to burn right click on the Start orb, then choose Windows Explorer.
3. When Explorer opens click on Downloads in the left pane. Scroll down till you find the ISO file you want and double click on it. Click on Burn Disk Image.
4. In the image below you will see Disk burner:, this should be set to the optical drive you want to use. Click on Verify disc after burning if you want to Windows to verity the disc image after burn. Click on burn.
5. In the image below you can see that the green progress bar, when the image is finished burning the bar will be filled.
6. After the image has completed being burned click on Close.
You will need a legal product code to make this installation. You will be instructed to enter the 25 character alphanumerical code, the installation will not continue without entering this code.