i have not installed any new drivers that did not come with windows 10 or the windows 10 minecraft upgrade.
Would highly suggest manually downloading the chipset, GPU, network, sound, etc. drivers from each component manufacturers' website so that you have the latest drivers. Default drivers that come installed with Windows (whether it's Win10, 8, 7, etc.) can be outdated fairly quickly and sometimes not stable anymore.
I can say neither I nor my wife have had any issues with Win10 and Minecraft, as we've both been playing just fine for the past 2 weeks every night.
I would suggest backing up the worlds and game files under C:\Users\<username>\AppData\Roaming\.minecraft
Backup that folder and copy it somewhere safe. Then remove / uninstall Minecraft entirely. Reinstall it, and once done then try to open up the game and generate a new world. If it works fine, then restore the items under the "save" folder from the backup you made and see if it loads. If it loads...then it was a messed up install. If it doesn't load, then it was a corrupted world and he'll have to start over.
i do not know about a launcher "FTB" . as a matter of fact, i am really unsure about this whole install. it does work, as i have been playing it. but when i launch, it launches as minecraft 1.6.48 . which then moves to 1.8.9 . which freezes the screen for about 10 seconds before it loads. ///
The 1.6.48 is just the Launcher version. When you click Play Game, it loads v1.8.9 which is the actual Minecraft game version. The launcher and game are separate, so they can be updated independently of one another.
