Technically it's too late to get Windows 10 for free. But there's an exception right now. If you use assistive technology (or are willing to claim you do), then they will still give it to you for free if you chat online and ask them. As for old computers with the license key. If Windows came...
Basically just put the CD in and reboot. If it doesn't boot from the CD you may need to press a key like f2, f3, escape, or delete to force it. Possibly even go into bios settings and tell it to boot from CD.
I'm pretty sure the Owner folder is her account's storage folder. You should be able to see the user folders all enumerated (listed) by default. Also "Owner" is the name commonly used by OEM manufacturers like HP/Compaq/Dell because they use scripted setup templates (part of the same routine...
Some folks in Neowin pointed out that this is intended behavior. Their article is here, and they reference this page of release notes. It appears this is to make Windows more like mobile devices.