Just press and hold the Windows hardware button and then press Volume Down (on the left side of the device). This is analogous to pressing Win + PrtScr and will auto-save the screenshots in the Screenshots folder in the Pictures Library.
If you are using Windows 10 (the OS used for this article), right-click the file and select "Open With". Select "Choose another app"; Notepad should be on that list.
There's no way you can open the backup with Explorer or using iTunes, only with third-party backup browsers. iMazing is good (at least I didn't have any issues with it...