For those of us who are not IT guys, how do I install Win10 to dual boot with Win8.1 on a SP3? What's the best (free) software to extract the IOS file to a DVD or USB? Does the setup (when I run extracted ISO files from DVD or USB) offer dual boot as an option? Do I have to partition my C drive to have a new partition for it or does it do that? Do I have to create a boot manager file? (I've set up dual boot systems years ago, but have forgot much of the details). Do I boot from the setup DVD or USB or do I run setup from Win8? (In the past I remember running setup in on OS only offers to upgrade, booting from setup disk had other options). Thanks.