Whats best zones and tactics to PL a lvl 39 Wizard to 55?

CoM should be pretty good til at least 50. It will slow down after that though

Karnors ?

dulaks harbor - if you know how to use reptile and your DS properly you can get to 46 easily.

Then if you pretty well geared head to PoI

if you have Darkhollow shroud to berserker or warrior, take them there, better defenses and better chance to hit something. With a berserker, just hit Maul for the most part, one hit is all you need, move to the next. Shrouding, I've found, is an awesome method for PLing any class