You can run it without a video card at all. That's the beauty of Xvfb.
Crysis itself runs on Wine, so does MWLL. However, the last time I checked (which was 2+ years ago) the graphics were glitchy as fuck. I'm sure that there has been some work in the meantime, but I can't guarantee that my old tutorial on WineHQ still applies.
also, 256MB EDO RAM? What kind of alternate universe are you from?