Hi Tracy,
You need to install the Video driver on your computer in order to have it working properly.
Here is the link to Intel site to download the driver:
http://support.intel.com/support/chi.../cs-009236.htm
Please note that your chip-set is "845G/GL" but you can see that on the list...so i would suggest to download both "845G" and "845GL" driver and try them one at a time, hopefully that's all you would need.
Cheers