Graphic Card Settings (Nvidia GF2 MX) Question

I have a Geforce 2 MX card and I am curious about one my my settings. Under the Direct3D setting I have the option of letting the card use system memory for texture rendering in addition I guess to its onboard memory. Thus far I have not let it use but 1 meg (this is the lowest setting available) since I don't have but 96Meg on board. I have been getting fairly decent frame rates for my antique rig. I am wondering if I would let the card use more system memory, would that help or hurt performance?I would also like to take a few moments to scold Microsoft. I know for a fact that my card handles OpenGL a lot faster than D3D, so why is MS still using this form of rendering when there is a much better solution? I think all these performace problems such as low fps, stuttering, freezes, etc. would be solved if they would give us, the end user, the option of dumping D3D and using OpenGL. Okay, I am done with my MS bashing (for what little good it will do).