First enter BIOS settings by pressing [del] key on the first screen, and then go to Adv. Bios settings and set First Boot Device to CD-Rom. Then, Re-boot your system, press any key to boot from CD on the second screen when asked to. Once you start booting from the CD, select fresh install, say yes, I want to install Windows on a drive that already contains an Operating System, on the next screen, delete the partition containing the operating system and then create a new one in the empty space. Then, format it with the File System you want and install Windows!