What program to wipe all unused space?

[The Old Fart]

My wife wants to get a better laptop but before I sell the old one I
wish to erase all of personal files that might have been on it. Even
though I don't expect any new owner to find any sensitive information on
it, we would prefer that none was left. I know that I could do a
complete reinstall of windows on it but this would entail doing hundreds
of Windows updates to get the machine up to date.

I know that I can easily copy onto a spare hard drive any files that she
would wish to retain for transfer to her new machine. I understand that
some programs can completely wipe the old disk of unwanted files. Most
of these programs will do this sort of wipe only on nominated files.
Programs like Ashampoo 'WinOptomiser 4' What I want to know is what
programs will do this sort or wipe on all unused space? Are any of
these sort of programs free ware?

 

[philo]

My wife wants to get a better laptop but before I sell the old one I
wish to erase all of personal files that might have been on it. Even
though I don't expect any new owner to find any sensitive information on
it, we would prefer that none was left. I know that I could do a
complete reinstall of windows on it but this would entail doing hundreds
of Windows updates to get the machine up to date.

I know that I can easily copy onto a spare hard drive any files that she
would wish to retain for transfer to her new machine. I understand that
some programs can completely wipe the old disk of unwanted files. Most
of these programs will do this sort of wipe only on nominated files.
Programs like Ashampoo 'WinOptomiser 4' What I want to know is what
programs will do this sort or wipe on all unused space? Are any of
these sort of programs free ware?

It's close to impossible to remove all traces of personal data...

just bootup with the cd, format the drive and reinstall windows.

Let the next person worry about the updates

(or else start the update at night when you go to bed...
it'll be done way before you get up)

 

[JS]

See: http://www.freedownloadscenter.com/Best/dod-erase-free.html
or
http://www.google.com/search?hl=en&q=erase+file+dod+freeware&btnG=Google+Search

JS