How to fix wow graphic problems?

Okay so ever since Wrath of the lich king came out i have had realy bad graphical problems throughout the game.The problems first start out with when im on the login page the dragon that flyes in and out of the screen , some of it body and face graphics flicker from being there and from being invisible so it looks realy funky.Next ones i log in all of my toons have the same problem not just on the charecter list but also in game with the graphics of the charecter shuttering so that i can not see the full image and it seems to do it at sertine angles. The worst thing that has been going wrong is that when i go into dal. i have no prob with lags but the graphics go all colorfull so that i cant see were i am going but i can see the map and my spells/attacks just fine and again this happends at only sertine angles. I have already opend a ticket and they said to do the wow repair thing i did that . . . no help. My computer is fairly new . it sais i have a 8x graphics card with 128vid. memory. so if you guys/girls have any suggestions i would love to here them because wow is just not verry fun any more since i have to deal with this problem thnx (=