My computer wont play downloaded demo

Hello,

i tried to play a downloaded demo of call of duty 2, however an error appears when I attempt to run the Call of Duty(R) 2 Demo? it states

"DirectX Error DirectX has encountered an unrecoverable error. Please check DirectX Help document for possible details."

then it takes me to another page which states the following.
A. Make sure you have DirectX 9.0c installed and properly functioning on your machine.

A. Please make sure that hardware acceleration is set to Full in your display properties as follows:
1. Right click the desktop
2. Select Properties
3. Click the settings tab
4. Click Advanced
5. Click the Troubleshooting tab
6. Verify that the Hardware Acceleration slider is set to Full.

A. Make sure that all DirectX features under the Display Tab in the DirectX Diagnostic Tool are set to Enabled as follows:
1. Click START
2. Click RUN
3. Type "dxdiag" and click OK
4. Click the Display tab of the DirectX Diagnostic tool.
5. Verify that all DirectX features are set to "Enabled".

A. Make sure you have the latest drivers installed from your video card's manufacturer.

i completed the steps to check on the acceleration and that the features are set to enabled. however it still doesnt work. i just bought a brand new dell with xp in april.

any thoughts?