please state why you want to format hard drive partition
(Do understand difference between hard disk and partition ?)
Do you have Toshiba Windows 7 recovery DVD set available ?
(or Windows 7 or 8 DVD (USB)) ?
Do you have a C: & D: drive (most Toshiba laptops have C: + D: (equal size) + small hidden recovery partition
(with recovery system builder files stored on D
formatting D: probably easy using Windows Explorer
formatting C: (boot partition) requires booting off Windows 7 or 8 DVD or USB memory stick
or some other bootable operating system disk
regards
Mike Barnes