General Points

What Windows versions my guide is for?

Windows XP , Vista , 7 and 8/8.1

What software I recommend? (some works starting with vista I have tested in Windows 7 pro 64bit VM)

In conclusion your computer is NOT obsolete, you can run it and use it in 2026 don't belive anybody telling you its insecure , we are using the internet not the magic force , internet attacks rely on ports open or vulenrable browser either that or you as the user install it yourself , keep you computer alive , save money and enjoy your life! and Happy Computing