I suppose for me PC's are like cars, I don't want to know what's under the bonnet, I just want it to work.
My wife has a laptop, I won't have one. My PC is an old tower originally owned by my son when he left home about 13 years ago. When I feel the need to 'upgrade' in some way I just pop along to our local Novatech shop and buy what I want or need. Over the past few years, I've bought two motherboards, some more memory, two hard disks (one inside PC, one outside PC) the discs with the narrow ribbon connection, not the wide ones and a small bank of 4 extra USB sockets. I bought Win 10 from Microsoft, downloaded it online, cost me £25 from some employee from Texas, he was the one I talked to and that's what he suggested, I just went with it. Works well and no real problems.
I use a few free programmes, like a virus checker and so on and it all works well.
I'm not a heavy user, just the usual, emails, I mooch around on it when I'm bored, need to plan anything and so on and I also watch a few films as well. I also use a VOIP phone attached to it.
My monitor is a 32" TV, perfect for me.