Very pragmatic approach. C# if you are ok with the Microsoft stack, or F# if you are a bit more advantageous and serious about the "new way of thinking". Python is also a great investment to solve real-world problems. And don't forget JavaScript. It is not just a browser language any more: there is node.js for the server side and it is the common language of most mobile frameworks that are multi-platform targeted.

You cannot go wrong with any of these. So have a look at code samples and spend some time browsing the web-sites about all of them then choose the one that appeals the most to you.