From NVidia:
Driver Installation Hints
* "Download Accelerator" utilities should be disabled when downloading any drivers.
* Do not run virus protection software in the background while installing the drivers. This prevents the driver from configuring itself properly.
* Before installing new drivers make sure you uninstall all NVIDIA display drivers from the Windows Control Panel. Browse to the Start Menu > Windows Control Panel > Add/Remove Programs and search for "NVIDIA Windows Display Drivers" or "NVIDIA Display Drivers" and select remove.
The Nvidia drivers are listed in Add/Remove Programs and can be uninstalled from there. You'll need to reboot after uninstalling them. Upon reboot it will detect New Hardware and search for drivers. It won't find any and report that there was a problem installing the hardware. Thats fine. That will come up a few times.
Then run the NVidia driver installation program and it will install all the drivers automatically and require a reboot.
You have a few choices for Nforce drivers. First is fromt he motherboard manufacturer. These may be a custom to your motherboard but may not be the latest. Then there's Nvidia. These are the latest official drivers but the latest Audio driver is a seperate download and has to be installled manually. Third is a Remix driver. This one has beta releases of drivers and it includes the very latest drivers available.
Nvidia:
http://www.nvidia.com/object/nforce_udp_winxp_5.10
http://www.nvidia.com/object/nforce_audio_4.57_win2kxp
Remix:
http://www.tcmagazine.info/comments.php?shownews=7744&catid=3
I've been using the Remix drivers and the sound driver has improved audio quality and performance nicely.