I also have the same videocard and core quad, xp sp3 and all updates und very often have the same error and crash, it's almost impossible to render 1 hour movie, and mostly it crashes on vitascene transition effect, when encoding with adobe media encoder it's crashes not so often as with canopus procoder.
Searched the web and found only this post.
I think some default settings or videocard itself cause it.
This is just a shot in the dark, but you might try disabling the PhysX nVidia application or even removing it completely, it does nothing for Premiere.
You have obviously used the ProDAD Vitascene on part of your Timeline. I've heard of very few problems with it, you you might want to do a test without that Effect, just to see what is going on. I use Vitascene a bit, and have had zero issues, but then I am applying it to SD material.
Though it sounds like you have shut down many of the "usual suspects," this ARTICLE might give you a useful tip - or you may already have done everything in it.
Good luck, and let us know how the non-Vitascene version works.
Have not heard of the PhysX for nVidia. Will have to keep this tucked into the back of my mind, and will investigate it a bit more. I've got 2 nVidias (one Quadro and one GeForce), and have not noticed this.