Well, one of the most user-friendly distros is Ubuntu, if you don't mind the Unity desktop. If you prefer a more traditional desktop, then Ubuntu MATE or Xubuntu would be pretty good choices too. Actually, the latest Ubuntu (16.04) will let you move the launcher from the left side to the bottom now too... that's a new feature. In any of these, if your install goes okay, you will want to install the "restricted extras" either during the install or shortly afterwards. You may want to use proprietary drivers for your video card for the best experience. Here are some ideas for you:
http://www.omgubuntu.co.uk/2016/04/10-things-to-do-after-installing-ubuntu-16-04-lts
Are you trying to dual-boot with Windows... Windows 10, or other? Ubuntu is generally pretty good at installing a dual-boot system, but there are some troubles you could run into because of the "UEFI" that replaces older BIOS systems. Anytime you are trying to install a new operating system, you want to back up any important information on your computer. If you haven't already, you should also make a set of "system recovery disks" for Windows in case you need to reinstall it. The "system recovery" might also save to a USB instead of DVD's, if you don't have a DVD drive.
Good luck!