Doom 3 crashes

I bought Doom 3 on Steam a few days ago, and it was running great until I reached EFD Junction 6, then after killing the enemies there, I turn around. Then the game crashes saying:

The NVDIA OpenGL driver lost connection with the display driver and is unable to continue.
The application must close. Error code 8"

I have to open the task manager before I can Alt-F4 out of the game.

These are the system specs:
Operating System: Windows Vista (TM) Home Premium, 32-bit (Service Pack 2)
DirectX version: 11.0
GPU processor: GeForce 9600 GT
Driver version: 275.33
DirectX support: 10
CUDA Cores: 64
Core clock: 650 MHz
Shader clock: 1625 MHz
Memory clock: 900 MHz (1800 MHz data rate)
Memory interface: 256-bit
Total available graphics memory: 1279 MB
Dedicated video memory: 512 MB GDDR3
System video memory: 0 MB
Shared system memory: 767 MB
Video BIOS version: 62.94.3C.00.00
IRQ: 16
Bus: PCI Express x16

Processor: AMD Athlon 64 X2 Dual Core
RAM: 2.00 GB
System type: 32-bit Operating System.

I really don't want to go back to the Xbox port because of how cut down it is.

You will find that the error message is telling you exactly what is happening. See if updating your graphics drivers solves it.