Your video card is not good enough for that game...it requires pixel shader and vertex shader at least 1.0 . Buy a better video card...there's nothing you can actually do about it...it is not software..it is a specification video cards have.
------------------------------------
A pixel shader serves to manipulate a pixel color, usually to apply an effect on an image, for example; realism, bump mapping, shadows, and explosion effects. It is a graphics function that calculates effects on a per-pixel basis. Depending on resolution, an excess of 2 million pixels may need to be rendered, lit, shaded, and colored for each frame.
-----------------------------------
A vertex shader is a graphics processing function used to add special effects to objects in a 3D environment by performing mathematical operations on the objects' vertex data. Each vertex can be defined by many different variables. For instance, a vertex is always defined by its location in a 3D environment using the x-, y-, and z- coordinates. Vertices may also be defined by colors, textures, and lighting characteristics. Vertex Shaders don't actually change the type of data; they simply change the values of the data, so that a vertex emerges with a different color, different textures, or a different position in space.