You didn't specified that before. Always be as clear and as detailed as possible when you make posts...
Anyways, with the "format" feature in Windows Explorer you always can choose to do a "full format" instead of a "quick format"...
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PS: There isn't any reason (much) why you specifically need a complete erase of your hard disk for your own use. Nothing will be wrong or will get corrupted or whatever if you simply choose a "quick format", and certainly not with a "full format".
A "quick format" will only format the FAT of your drive. This is all which is needed to ensure a working blank hard disk (if the drive was formatted before).
Any data left on your hard disk (after a quick format) will simply be overwritten when needed. The physical bits and bytes which still might exist doesn't exist anymore for Windows, so there is absolutely no harm (or reason) why you explicitly need a full erase (for your own use). It has absolutely no disadvantage for Windows when the hard disk wasn't completely erased.
A "full format" will also set each byte on your disk to 0, making recovering files virtually impossible by normal means (means accessable by you and me. Though there are high-tech ways to maybe still recover some stuff, but this is only possible with highly specialized and highly expensive hardware methods). Which is more than secure enough for every day (and more) usage of a hard disk.
If you want it for security reasons, eg: you're gonna sell/give the hard disk away, see "
CookieRevised's reply to Full erase" first, and after reading and understanding that post, read the full thread...
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