I never play dota2 but dota 1 i already play it. But for now i will choose lol LEague of legends because im addicted to it.
dota2 is most popular from these games, and it is awesome. But the problems are:
1. you may start hating people if you play without your team
2. too many crazy russians who play realy bad and scream all the time
Is just like here in my country that they scream when they play and sometimes they crazy and talking trashtalk when playing..
In comparison with CS Go its nothing, trust me

In LoL it for example depends on what server you play. I used to play on West, tried EUNE and there were lots of toxic players.