Windows 10 is the new one and M$ is trying to get me to upgrade from Windows 7. 7 has the benefit of running like XP use to and you older programs will not run on 7 but not on 8.
In your case sounds like you would not have any old programs to run but I'd go with 10 Or 7 if you can. Get the most RAM you can afford and a large, greater than 500 gig of Hard Drive. Think of hard drive as you storage or file cabinet and RAM as you desk top which allows you to have several programs open at once.
HTH