If you can't boot disks
most of the time it's due to User failure. Set DVD drive first to boot in BIOS setup, then HDD, Save changes, exit. How to Boot A Computer from CD or DVD - YouTube
Place DVD/CD in drive, reboot. Do you receive the prompt to "Press any key to boot disk?" If not the disk may not be burned correctly. Try ImgBurn
at 4x speed. Or try tapping the key given on first boot screen for one-time BIOS boot menu to trigger disk.
Reset the BIOS to defaults after taking note of SATA controller setting: Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS
. Try disk again.
Try booting flash stick installer which should be listed in BIOS Boot order or Boot Menu under USB, Removable or HD's for: OS repairs or reinstall, WD disinfection, Partition Wizard repairs. If these fail try unplugging DVD drive.
As a last resort you can replace the DVD drive, or rescue your files with Paragon Rescue CD which will boot itself, then boot Partition Wizard bootable CD which will also boot itself to wipe the HD
, which will in turn force the installer to boot itself for reinstall.