Star Wars: Knights of the Old Republic failure: cause?

I have installed Star Wars: Knights of the Old Republic on my Dell Inspiron 1501 Vista Laptop, however, whenever I run it, it stops working. I have heard a rumor that this is because I have an ATI Radeon xpress that doesn't support OpenGL, which is what SWKoToR is written in, but I have also seen in other websites that Vista fully suports OpenGL. I have updated SWKoToR to version 1.03, which is the last version, so that is ruled out. If someone out there has an answer, please let me know, I REALLY wnat to play Knights of the Old Republic. Thank you.