..easiest team focused for a non gamer who wants to be useful.
ice/kin (i'd choose corruptor)
rad/kin or dark/kin might also be of interest (these avoid knockback or scatter powers, dark/ provides an additional heal while rad/ does a lot of debuffing)
If they want more of a smash type character it is hard to go wrong with a super strength/invulnerability brute. It's a good character to learn the game on.
/Willpower or /Shield if wanting to avoid how Rage works.
Just my 2 cents. Nothing wrong with many of the suggestions made so far, though I might suggest leaving arachnos soldiers and widows for after they get a little experience.