Win 10 is better but it is always better to be with the latest version because lots of new technology comes up daily. From Solar Light Pipes Technology
OS which are mostly used are Windows 7 and Windows 10. I have used both windows 7 and windows 10. I think Win 7 is light weight and good to use whereas Win 10 is kind of heavy and makes your pc slow. It occupies a lot of space on disk and needs a lot of ram space. I went to Win 10 and have come back to Win 7.