This is a free eraser program to wipe the drive clean and you won't have to worry about private information being retrieved later on.
http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2004-21,GGLD:en&q=killdisk
Then reinstall your operating system if you plan to give those disks with the computer..otherwise leave it blank and let the new owner install their own operating system.
TONI
Giving my PC away but want to wipe out all files except typical operating and MS programs. Is there a good file clean up program out there that's easy to use, doesn't take forever and works?

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