The difference between damage is not that big.
pro's; lightining-> -hit more mobs around you
-able to stun
-nice nukes
con's-> hit more mobs around you (since your full int you can get mobbed)
pro's; cold-> -like you said your self, mobs dont have restistance against cold
-Freeze!!!

-Slows enemy's down.
con's-> - i can't find some con's, some say's its weak i personally prefer it.
It's wich suits you the best but i can tell you to stand vs an ice nuker is annoying xD