jrodfry :
I meant to say that I will be keeping the hard drives within their original computer/laptop, and just deleting personal information.
Thanks for the help
It depends on how thorough you want to be in removing personal information. If the removal needs to be 100% certain then the only method I see is completely reformatting with a program such as Derik's Boot and Nuke and reinstalling the OS.
To my knowledge there is no program that would execute the type of erase your looking for. There's a program called
eraser that permanently deletes files that could otherwise be recovered; but the program is only as good as the human behind it. Because we're all fallible I wouldn't recommend using it; undoubtedly some data would be left...