I fear chaps that computers are becoming ever more commoditised, and therefore tending to be jerry built, Apple not excluded. Even if you buy separate bits and plug them together like I do you still cannot guarantee things will last. Take memory for example: I had never had a memory bank fail since my first PC almost 30 years ago . . . until recently. I also had a rather expensive (Asus) graphics card go belly up. The former chips were replaced under warranty, the latter not as it had gone past the warranty period.
My 2 cents for what it is worth. You're doing mainly photography, so you want decent monitors and graphics cards. A graphics card with 2gb ram as a minimum for optimal performance, Geforce 730 or higher, AMD R9 or better. The graphics handling in W10 is very good, so don't worry about the OS. You'll be better off with the fastest processor you can get for the money, so go for an 8 core or more if you can as just about all recent photography apps use multi threading. As for memory, the more the merrier. An SSD or hybrid drive will help with start up times. Disk drives are a cheap as chips, so don't pay too much extra for a larger installed drive you can always add more storage later. If you are thinking of using external storage make sure you go for USB3 ports and drives, they are a lot faster than USB2.
Card readers cost about £5 on eBay, so all you need is a spare half slot.
Alan, Vista is no longer being updated, but it shouldn't cause you too many problems if you steer clear of those Russian websites featuring ladies of ill repute. It still runs Windows defender which is a perfectly adequate basic protection. So don't rush into anything. Our daughter's machine still runs Vista, being my old one and the best part of ten years old.
Paul the Medion PC - looks good value with the one small exception that all of the SATA ports are already in use meaning you can't add another internal drive. Probably not an issue for you. It wouldn't put me off to be honest, it looks good on paper.
The PC world one, OKish.
The Ebuyer one - no - the graphics are not going to be good enough. That said, my PC came from eBuyer - but in lots of separate bits

Alan, Novatech. I looked at them before I built a machine myself. Their stock builds are a bit basic in one or more area (the operating system is extra, for example) and the cost quickly mounts up as you add customised components. Not ideal for a tyro.
I've still got at least three years to go on this machine, or is it two? Anyway it'll do for now and I would never be able to get the FD to sanction the purchase of another one just yet.