If you're playing competitively/multiplayer there's a basic rule of thumb for any game that you usually go with the lowest graphics. When I play C2, I put every to high (which is low, lol), turn on DX9, and disable the high res textures. I also use several cvars that lower the graphics even further just so that i can get somewhere in the neighborhood of 130-150 FPS, taking advantage of my 120Hz monitor. I outline the cvars in this video: