Hello Adrian,

Windows 7 does not offer full screen magnification. If this is what you need, do explore ZoomText 2019.You can download it from:

https://support.freedomscientific.com/Downloads/ZoomText

It runs in a 40-minute demo mode. Not portable. That version is sold in a USB stick.

Windows 10 offers some high contrast modes and colour filters. Unless you need a peculiar colour scheme, I do not see why you need ZoomText. When it comes to screen reading, NVDA gives you much more than ZoomText can.