Windows 10 is currently the latest operating system from Microsoft. The major change that it brought back was the start menu which was missed by many people. There are some other benefits of upgrading to Windows 10. Along with the benefits comes certain issues that you may face after upgrading to Windows 10. So I have included this infographic, which covers all the points that will help you in understanding things in a much better way. These all things will help you to take the decision, should you upgrade to Windows 10 or not.
First thing it starts with are the reasons you should upgrade to Windows 10. Then it mentions certain problems that you might face after upgrading to Windows 10 which can be totally avoided if you know them before. And lastly it ends with certain hidden features of Windows 10.
I hope that this helped you to know most of the major things you should know about upgrading to Windows 10. Regarding the problems that are stated above, you can always take the backup to avoid data loss. And if you want to have more space in C drive, you can go ahead and delete Windows.old folder if those things are not needed. Personally, I recommend you to use Windows 10 as the UI and everything looks modern and easy to use. If you want to use a previous version then I suggest that Windows 7 as it is quite stable but Microsoft has pulled the support off. If you have any doubts please mention them in the comment section below.