Hi and welcome to LQ.
Have you decided which Linux distribution you'd like to download?
Have a look at this description of 10 most popular linux distribution and choose one that sounds right for you and report back here.
At this point do NOT stress too much which one it is. Any distribution from the most popular ones will do. Over time you will change it. You'll try a few until you come across the one that is 'best for you' but we can't know which one it is. You'll have to try them out and see for yourself. I don't think there are (m)any people who have stayed with the first distribution they've ever tried.