[ubuntu_mate] Recovering windows..

As your thread is really a Windows question unrelated to Ubuntu I have moved it to the "Windows" sub forum.

Generally the answer would be yes, as long as you have the Recovery partition unharmed and intact you should be able to reset to factory default. I would create exteal recovery media as a backup and also possibly take an image of the disk as it currently stands. Don't take this as definitive, it is only the opinion of a someone not using Windows, I'd suggest posting at the HP support forums.