mage was my first character. if i were you i would choose fire, cuz it does more damage to enemy. i can explain a little bit: fire means more damage to health, you can kill your enemies a little earlier and easier. frost means damage to health and stamina, you can damage your enemy's stamina and enemy cant use any power attack on you. shock means damage to health and magicka. if you attack a mage, this means enemy will use magicka, you can easily get rid of him with shock spells. btw you need to get a second way of destruction, because there is some creatures or people have resistant to fire out there. the other destruction classes have same issue as well. sorry for my bad english.