Hi Peter,
First of all if you are happy with Windows 8.1,I would be hesitant to pay for Windows 10 at this point. I still think Microsoft is going to offer one more chance to allow the initial dissenters a chance to get on board. It may not be free, but at a reduced cost.
If you do decide to upgrade the only way to do it right is to download Microsoft's Windows 10 Media Creation Tool. With this you will install the Windows 10 bits and the Linux booting files on a USB flash drive. Then you will just install the drive while the computer is running and click on the setup file. Then you will go through the process to upgrade your Windows 8 to Windows 10. You can choose to keep you files or do a clean install. I would choose to keep your files. If all is fine when it completes and everything works, good to go. If you are having any difficulties your motherboard ID is now registered and you can do a clean install if you need to. Just boot the computer from the USB drive and do a clean install.
I have upgraded nearly a hundred units now and the only failures that I encountered were the ones that customers tried to do over the internet.
I have upgraded computers that had the user files folders moved to other partitions and even other physical drives and the upgrades where keeping the files was chosen all operations worked perfectly. In my opinion the variability of the internet is the main cause of most of the upgrade issues.
One thing to remember is that you need Windows 10 Pro if Group Policy Editing or encryption is necessary for you. Registry mods were able to partially restore gpedit to Windows 10 Home previously, but the version 1607 update has taken this option away, otherwise Windows 10 home does everything that the average user needs.
Regarding drivers, my experience with Windows 10 installing working drivers has been nearly flawless. Better than any of the previous versions of Windows. Yes I have had issues with older peripherals not having drivers installed. That isn't Microsoft' problem, that is the vendors fault because they refused to write drivers for Windows 10 or 8. In this case just install them in " compatibility mode" as either Windows XP or Windows 7, depending on which system the driver was written for. I honestly can't remember a driver that didn't have a Windows 10 version that I wasn't able to get working by installing it in compatibility mode.
Regarding how it works, many users are just paranoid about any change. You can do anything you want in Windows 10 that you did in Windows 7. Just right click the start button and there is everything, including your shutdown options. Miss the old Programs button that was on Windows 7? All you have to do is go into "change folder and search options" and uncheck hide protected system files. You need to do this to make the Program Data folder visible. Now just right click on the taskbar and choose new toolbar. Then open the C: drive and go to Program Data>Microsoft>Windows>Start Menu> Programs. Now you will have a double arrow tab on the taskbar and when you click on it the menu will look just like the old Programs menu
in Windows 7.
Maybe the outward appearance of Windows 10 doesn't seem to be significant, but the improvement to the OS itself is. Better color rendition, better networking, better security and the most stable Windows Kernel ever.
The changes in Windows is not going to cease. They will continue to correct security and operational issues and try to improve features, although the room for improvement to features eventually runs out as there is only so much that really is useful. Having Windows 10 puts us in a perpetual loop where upgrades don't cost us anything and that may be the best reason to upgrade to Windows 10 now, because I think that it is inevitable that operating systems are going to eventually go the route of other software, such as Adobe Creative Cloud, and will be available as a yearly subscription only. Eventually this will happen. I know all of the Linux people will say just switch to Linux, but there is a reason that Windows stays so relevant and even Apple can't really make a significant dent in Windows usage, and that is because if you have Windows, everybody writes their software to work with Windows because the market is so huge and they are reluctant to spend the money to develop for the limited market of Linux and Apple.
I'm one of the people who missed the deadline for the free upgrade to Windows 10. Long story short, I procrastinated and was traveling overseas on the expiration date and forgot all about it. Of course, no one to blame but myself. I was planning to wipe my desktop clean and start fresh with Windows 8.1 again, but since I was going through that process, I figured I might as well move on to Windows 10. However, before I go download and pay for it, I'd like to get your opinion on it since many people have been using it for quite some time. Do you love or hate it or are you somewhere in between? Any reason not to upgrade to it? If I do get Windows 10, do you recommend that I do a clean install from scratch, or should I install it directly over Windows 8.1? My system hardware requirements are more than capable of handling 10, and my software programs are fairly current so I'm not worried about the incompatibilities. Thank you for your feedback.
--Submitted by Peter M.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic