If lets say i have a monster with hexproof on the feild and i play wrath of god, is my monster destroyed?
Yep. If a spell refers to "all" of something, no individual permanents are targeted. The effect of WoG simply applies to all creatures.
{Wrath of God}
No, hexproof does not protect against boardwipes, hexproof just makes it so the creature can't be targeted with spells and abilties from your oppenent. As WoG does not target it will still kill your creature.