Being a Newbie, I hesitate to pitch in here and will probably get flamed, but here goes.
Spouse and I retired from IT a few years ago - he was a project manager in software development, I was in charge of a Helpdesk and was expert in Windows and MS Office. We have just bought a cheap Win 8 laptop (what a dog's breakfast that is) and I have a Win 7 one, but the rest (!) of our machines run XP and will continue to do so until I bin them.
Most of the features of Win 8 are superfluous: I downloaded Classic Shell and now the new ones behave like Win XP. If I want the rest of Win 8 I'll turn to my Android tablet and smartphone, thanks.
I tried Linux years ago and decided to stick with Windows as getting hardware and software to work with Linux then was not worth the work. Yes I have a raspberry pi as well, but not as my main machine. End of the Linux story for me so I will not get involved in further discussion as to Win v Linux merits.
Most users have Windows and don't want to learn new IT skills. For me a new laptop is a thrilling new toy. While spouse is away I'm demolishing a ThinkPad to change the fan, more fun than the ironing. Most users just use computers as tools, and are afraid of losing precious photos and files: Microsoft have played on this fear. I strongly believe that it is most important to back up your files regularly - monthly rather than annually or once every few years - onto an external hard disk which lives in a cupboard between backup connections. Few of my friends have ever done this, I do it fortnightly onto one of two disks. Paranoid, yes, but I have files going back decades.
Malwarebytes is free, and works. Ditto Avast. Using Chrome or Firefox instead of IE is less risky. My filing is safe. So I'll keep XP running on the older machines, online, or I won't access the anti-malware and -virus updates. If you really must buy a new laptop, look at e-Buyer and order a nice cheap Asus or Acer with Win 8 and install Classic Shell. Laptops have never been cheaper, and external hard drives (usb) cost far less than the pain of losing a generation of photos.
As Peter says, it's only worth investing in something your partner will be able to use, or your kids. How else will they sort out your affairs now we keep so little in bureau drawers (apart from a stack of backup disks, that is)?