Hi
If the problem relates to Windows not being able to partition or format hard disk it may be because
Linux (some versions) on the hard disk cause Windows (most versions) not to access the hard disk because of what Windows considers to be a corrupt MBR.
Try booting from Windows 7 or 8 DVD, find option which allows you to delete all partitions
then reboot and start install again with Win 8 DVD (or USB memory)
If this does not allow you to clear all partitions then you need software which can wipe the MBR
DBAN is Linux based and it wants to wipe the whole hard disk
or similar software on a bootable CD or USB
( I use a Win PE CD with MBRWizard)
regards
Mike Barnes