Well from what I understand @Desu
you would get three (3) choices on what to do.
1: Upgrade and transfer EVERYTHING
2: Upgrade and transfer only personal files
3: Fresh and Clean install
Also from what happened to me on both my Desktop which I did only a personal file transfer (running Win 7 Ultimate) and my Tablet with a Fresh Install (running 8.1) they both made a windows.old file and everything that was from the old OS was there including personal files, app data and program installations.
I had no problems with win 7 > Win 10 and everything works... No extra drivers needed. My Tablet on the other hand ran into an issue where I couldn't do anything because the touch screen was disabled by default... Once it had restarted it worked...
There was some UI lag though when I would try to play my Clicker Heroes game with my auto clicker by when I would start it and after 10 seconds I had stopped it but it would keep going for another 3 seconds then it would then stop.
Tablet had driver issues with the sound and Bluetooth but were fixed after some 14 updates
Desktop had no other issues after 2 updates.
*update* after I had installed Sony Vegas Pro 10 it would not load and would come up with a .NET run time error. I could not install any other .NET because it's already installed a newer version...
VLC had codec issues with .mkv but I was latter told to change some settings and it worked fine
I think that's it for now.
P.S. The xbox app is SO FREAKING COOL! I had trolled my xbox one friends after I had joined there party and I was also on my 360 and they were SO CONFUSED! lol
If you had connected your Micro$oft account and you had friends on the one you can join there parties and actually talk to them.