I never install closed source OSs on other people's PCs anymore. If they want to use windows (or OS-X), they are on their own, Im sick and tired of providing support for it. Endless viruses, malware, DLL hell, not being able to SSH in to do anything, .. nope, not me. If they got a windows problem I tell them to take it to the shop or use their OEM or MS hotline support.
Ever since I switched to supporting ubuntu only, the time I spent on helping others has dropped to almost zero. Every 6 months or so I get a phone call asking if its a good idea to upgrade to this new version, and thats essentially it. Honestly, if it werent for those few occasional questions I would have sworn most of them stopped using the PC or reinstalled windows themselves, but nope, people manage just fine.