They are both awesome ,and maybe best builds in game ...
I had them both , lv.7x ...
Warrior:-Ultimate Defense (Seriously , Ultimate)
-Great tanking ability
-Can kill great , but he has hard time sometimes
-Slow (You'll get irritated by that)
-example: When you go help a friend in trade , NPC thieves spawn,
you'll have hard time chasing them, no matter if you 1 hit them
-Has a hard time powerleveling
Wizard:-Awesome Damage
-Can hunt uniques
-Can kill anything 10 levels above him
-Dies really really fast , not even bless helps you sometimes in PvP
-Arsenal of AoE damage
-Teleport

-Best powerleveler
Overall ... depends what you want ... I, myself , perfer 2h , because Wizards seems really unstable to me ... You will never be able to rush in group of 3-4 thiefes , and kill everything.