Disabling anisotropic filtering in game and using hardware profile for it
Using the newest Nvidia driver that just came out
using nvidia profile for max performance
I have an ASUS p5q pro MB so I uninstalled the sound driver and found a new realtek driver that seems a lot more stable (HD AUDIO) Using the lowest of the 24 bit settings on it and no effects. think this was a big one
I already have UAC disabled and use classic UI settings (no aero) in vista 64 bit
Use the newest EVGA tool to max out my 285 GTX fan to make sure there are no heat issues from this unoptimized engine.
used bloom instead of HDR

I don't use the famous .dll though I tried it

There are still a few scripting bugs that cause crashes. but they are few.
this game is extremely finicky and any number of software conflicts can crash it especially on vista, win 7 and or x64 systems.
I'm now getting pretty smooth frame rates nice game play and very few crashes. The crashes I do get seem to be script related. for example the guy from The King runing up to me to give me stuff by the north freeside gate often causes a crash. Using a workbench no longer crashes me but does cause audio anomalies like it would crash but the new driver resolved it.

I may have left out a couple windows tweaks I read on the forums but don't think they affected me.
So if your hardware is similar and you haven't done these things try em out. Esp. the nvidia and realtek drivers. and any fan speed tweaks.

Vista x64 home premium
4GB ram
GTX 285
ASUS P5q PRO

I wouldn't hold my breath that they ever make this game engine more robust. Probably many problems can be solved my more work that should be required of a gamer.