I have an oldie - laptop DELL E6400 - that I want to give my mother-in-law as a replacement for the desktop she was using in her work (she has her own business, so office and personal use, but nothing fancy), which in turn breathed it's last a few weeks back (Dell GX240 or earlier).
Laptop originally came with Vista Business, but I never even once booted it with that OS. I had Pro versions of every OS that came later - 7, 8, 8.1, 10 installed and used on it. There are drivers available for Windows 7 for this laptop.
So on one hand Windows 7 would be the least problematic option, but on the other hand it will not be supported for long by Microsoft, and drivers already are not developed anymore by vendors. That would not be a problem with just office use, but small business owners need to count their money and I can easily see it used in home. Therefore there is a need to look at other WIndows versions, but here is where it gets complicated.
From my own experience there are certain applications that while giving impressions of simple program, in fact rely heavily on either (or both) functions of the Operating system available only - or greatly improved - in newer versions and/or devices that offer some additional functionalities beyond basic.
To further explain what it means using real-life examples: laptop in question has a Powershare option for USB port, which means that you can use it as a powerbank for any usb-charge-compatible device. While you would not take it on a hike in the mountains, I routinely had it on vacations and whenever it was nearby I used it to charge all my stuff. I used is as a backup for pics and vids from said holidays - 1080p means that even 128GB SD will be filled quickly. I used it to boost wifi signal by running Connectify in repeater mode so that we could use our mobiles while vacationing abroad (why pay for calls to family when you can use whatsapp?). I used it to convert videos of my kid I made on the beach so that it can be sent via email to her grandma to swoon over her ingenuity with a sand beach shovel...
But upgrade to a newer Windows version and suddenly Connectify doesn't work because driver doesn't support hardware function of the wifi adapter. GPU cannot be used anymore to do fast conversion because DirectX version supported by this newer windows does not support older DX implementation in the VGA adapter. And so on. Which is very annoying, because even if this laptop is 9 years old, it is - in current configuration - at least as powerful as any new laptop you can buy for £250 while worth about half that.
I think there is a reason why around 50% of computers used in business worldwide still run on windows XP.
SO the question is: how difficult average user will find using old hardware with newer software? How probable is the situation when after another update (be it windows, driver, installed software) something either doesn't work properly anymore. Or at all. On the other hand - what would be the strong points of running newest software on old systems? Platform stability and security is obvious, so how important that would be in office/personal use and would that outbalance some loss of existing functionality? Virtually no computer running Windows 7 was a victim of this year's ransomware rampage, so that is a big selling point, but is there something else?
