I also used the Windows 7 for as long as possible... but if you look at some of the really newer games they all recommend Windows 10 or at least 8. I don't know why since I am not an expert on OS but I decided to upgrade to the Windows 10 when they were still offering it for free. I waited so long to make sure that they would eliminate as many bugs and glitches as possible. When I switched over, I expected the worst but was very pleasantly surprised. Upgrading was really easy. Nothing got deleted, all remained as it was.
You will, of course, notice the new interface design and small extra features. They seem to be putting more and more emphasis on the connectivity with social media platforms. Overall, I don't regret to upgrading to the Windows 10. My computer runs great, it feels way faster than on the 7 and I really love everything they've added.