I use a program called image for windows.
It is not free although,
It works perfectly fine and is nvda friendly.
It is a disk imaging utility and backups your entire drive to a single image file,
And it is mountable as a usb drive once it is complete.
The program costs around thirty nine dollars and when I boght it it came with a three pc licence.
They do offer a thirty day trial.
Let me know if this helps out.