I believe the biggest difference between Linux distributions for beginners will be the DE (desktop environment), you can change it in any distro you choose, but usually there is a DE that is optimized or customized as standard for each distribution. Some DE are very different from the Windows interface. I highly recommend using Cinnamon, Mate or KDE, the transition from Windows to Linux will be smoother in my opinion. The DE also includes a suite of applications such as an office suite, browser, administrative and customizable tools, which will also impact your experience. As other said before Linux Mint is a great option, it is stable and friendly. There is LMDE which is Mint with Debian under the hood instead of Ubuntu if you care about use a non-enterprise based distro, but that is another discussion.