I am not sure if this is the right forum for this question. I am buying a new computer running Windows8. I need to dispose off my old laptop and old desktop both running WindowsXP. Since I have very important personal info in both the old computers, I want to completely destroy all data (wipe the hard drive) before I dispose them off for the peace of my mind. I know clean installation of Windows automatically formats the hard drive, but I want more safety so that even a professional bad guy cannot recover any info from my computers.
I have two questions in this regard. Which free software do you recommend for this purpose which is not only totally reliable but also relatively easy to use? I would say I have medium knowledge about computers. I cannot handle software that are too technically demanding for use. Secondly, it would be helpful if you can outline the exact steps for using this software. I have never done this kind of work before. After downloading the software, do I have to install it first? When I have saved my data or transferred my data to the new computer, can I use the data erasing software straight away or do I need any other preparation? How long does it normally take to wipe a medium size drive (280 GB)? And lastly, can I re-install Windows XP after the hard drive is wiped clean (I have the necessary keys). Without the operating system installed, nobody will have any use of the old computers, right? What do people usually do when disposing off (selling or donating) their old computers?
Thank you for your help.