Mr_Dr_Oink

Great points.

But i feel like they apply more to people who are already using linux. For those struggling to make the switch i would argue ease of use and familiarity are key. Mint and ubuntu are a great place to start.

You are right though.

Newbies

https://linuxmint.com/

https://ubuntu.com/

Experienced

http://fedoraproject.org/

http://www.debian.org/

Advanced

https://www.kali.org/

http://www.archlinux.org/

Or just shop around. Its free and its better than windows

Also a raspberry pi with raspian is a great place to start for cheap. https://www.raspberrypi.com/software/operating-systems/