Windows 8 is OK, the new tablet style Metro interface seems somewhat silly, but I suppose one could get used to it. You need to eliminate a lot of junk and just have spots for important stuff, then figure out a way to get to all of the occasionally used stuff you have on your machine, and it would be fine. Probably better just to make Metro interface optional. If you flip over to the desktop side, it's basically Win 7 without a start button.
Actually, I did move the immunization machine from one computer to another (dual to quad core, more memory) easily. I started by simply referencing it on the dual core hard drive, but it seemed slow and occasionally would not start. I then copied it over to the main hard drive of the quad core and it ran well. It had to reset new settings (new device as monitor and something else that escapes me at the present) when Win 2000 opened up. I suspect XP or above would have requested reactivation with this amount of change, but it ran well.