Hi all. I have a laptop that with your help I set up to dual boot (using Grub) to both Ubuntu & Windows 10. I have now treated myself to a new laptop and I have replicated your instructions and all is well. However, I wish to return the previous laptop to a Windows only machine, to give to my wife, without factory resetting it (I'd really like to avoid setting up Windows again from scratch). How easy is this to do? I guess I need to alter the bootloader to bypass Grub and somehow reclaim the disk space that is currently allocated to Linux. Can this even be done?

Idiot-proof instructions if possible please.

jono