I find for my relatively minimal and non-intensive work (like processing the occasional image for web, making CD's for relatives, etc.) a Win 10 computer works all right. I have a little Samsung Win 7 "netbook" that I use for traveling, and for the Nikon programs mentioned, it's dead, dead slow. To time the loading of a D7100 Raw file in Capture NX-D you'd do better with a calendar than with a clock. Copying files is best done before you go off for dinner in hope it will be done when you get back. It works, but I only keep this computer going because it's very small and very rugged, unscathed after over ten years much of that traveling the world in a backpack, and it handlers file transfers and saves easily if slowly, and it's just fine for email.
By comparison, the same programs work reasonably well even on my bottom-line 3-core Win 10 laptop. This one, a Dell, also has a pretty minimal display, but it's well ahead of the old Samsung. I'm not a serious tweaker of subtle colors, and I can be fairly sure that an image that looks OK on this screen will look OK just about anywhere.
I think many people here do a lot of heavy-duty processing, and for that I'm sure such a rig would be a no-go. But for the kind of thing the OP seems to be looking at, I think nearly any Win 10 computer now available would probably be a good step up, and at least usable with the software mentioned as well as other programs.
I've used Linux too, and that has the advantage that you can put it on just about anything, and can even boot from an incorruptible DVD. The open source programs like Darktable and Raw Therapee and Gimp (which also work well on Windows) are fine, but installing Windows software, though theoretically possible, can be a pain, and I had poor success.