Since I had to go for a new PC I decided it was worth giving Windows 10 a shot, plus Win7 support has ceased anyway.
I thought it would have been nice to share some stuff you might find useful in order to deal with some common issues you might encounter.
1) What happened to Windows Experience Index?
Microsoft removed the graphic version of the Windows Experience Index in Windows 8.1. But the underlying tool, the Windows System Assessment Tool, lives on. Better still, you can access the old performance ratings easily.
Here’s how you can check your Windows Experience Index on Windows 10.
The Winaero WEI Tool is a basic but handy tool you can use to generate a visual Windows Experience Index. Winaero WEI Tool is lightweight and takes seconds to give your system a score. It has a few handy screenshot tools built-in, too.

2) Windows 10 Won’t Connect to Wi-Fi
Provided you have broadband Internet access, a Wi-Fi router, a Wi-Fi module properly installed on your PC, in my case I had to:
- forget the Wi-Fi network, by clicking on the Wireless icon in the system tray and then right-clicking on your current network's name, then choose Forget
- disable the wireless adapter's power saving feature, which you can do by right-clicking on the Start Menu and choose Device Manager. >> Expand the list below Network Adapters. >> Right-click on your network adapter. >> Select Properties. >> Click on the Power Management tab. >> Unmark the checkbox next to Allow the computer to turn off this device to save power.
- set the Wi-Fi network’s channel width to 20 MHz, which is done by pressing Windows Key + I then select Control Panel >> System >> Device Manager >> Network Devices >> "Your Wireless Adapter Name"; right-click on its name and select Properties, then select the Advanced tab and from there choose a Bandwidth value of 20 Mhz Only
- set the Wi-Fi network's channel to either 1, 6 or 11, which is done by logging into your router’s portal and locate the channel setting (I can't help you there since the steps required differ for each manufacturer). I don't know why, but Win10 seems to have connection issues with other channels.
3) Windows 10 minimizes my full-screen games/apps at random
So far, this has been the most annoying problem of them all. If you look on the Internet there are plenty of people with the same issue, and a gazillion possible solutions.
After having personally tested a lot of the suggested fixes just to find out none of them worked, I stumbled upon this useful tool:

Basically, what happens here is your running task/game/app gets minimized because of some interfering background process, the problem is determining the offender and kick its ass. That's what that tool has been made for, this guy wrote a program to show you which application is stealing focus. Just run the program, then play the game and when you lose focus look at the process name that is printed in the dos box. In my case the problem was related to M$ One Drive, which I disabled from the list of start-up programs.
4) Process Explorer
Here you can download an enhanced version of the Task Manager, with a lot of extra infos and stuff:

5) New Windows Update interface sucks
It really does! You can no longer select which updates to install, moreover it just shows you one update at a time, and if you don't install it you can't see the other pending ones!
But do not despair! You can download this troubleshooter, so you will be able to hide unwanted updates or show all hidden updates, you can find it here:

>> To Be Continued <<