I would choose Kubuntu for its normal Windows 7-like start menu (incorporating type-search for applications, and organized submenus). The distro also has several things to get you rolling, optionally installing flash and mp3 proprietary extensions, a driver installer to get proprietary things like ATI/Nvidia and WiFi up and running. Firefox and LibreOffice are ready to go, and typing "updates" or "software" in the menu will get you more programs to install.
In 17.04 (beta 2 from a few days ago) the awkward "K" branding has been removed from KDE plasma, giving the startup and menu a more unified feeling.
At noob level, probably the most challenging thing is to make and use a bootable USB of the distro, and for that, the ISO plus Rufus or Unetbootin will make the flash drive, and creative pounding of function keys on boot will get your PC to start live off it.