Don,
If you click on the link below it will take you to the manufacture (Nvidia) of your graphics card. There you can download the latest version of drivers.
I just checked, the latest version for your system is 196.21, released on January 19, 2010. Windows 7 is a new operating system, so it is best to use the latest drivers available. Make sure you select the 64-bit version when making the the choices for your system/graphics card.
You also have the option of downoading them from Dell's support website, but they are usually
at least one version older than the manufactures website.
http://www.nvidia.com/Download/index.aspx?lang=en-us