"Important Note: This product requires the Shader Model 2 which is a feature of your Graphics Card. Please make sure that yours is equal to or higher than the cards mentioned in the System requirements below.
Windows XP or Vista
2.0 GHz Intel or equivalent AMD processor
1 GB RAM
Nvidia Geforce 6800 Series, ATI Radeon X850 or S3 Chrome 430 GT graphics card (minimum 128 MB VRAM)
Download-Size: 220 MB
Installation-Size: 1 GB "
This is taken from the web page of that game. Your computer does not meet the requirements.