Considering my Crappy Integrated Intel Video Card.?

Well everybody says that the Integrated Intel Video Cards (Intel GMA x4500 HD) are horrible for gaming, so I decided to test it out by downloading a free demo of Bullet Storm. (Note: I don't really care about graphics) Anyway, so I downloaded, and it runs perfectly fine, just a tiny bit of lag. My question is, if I get a better graphics card, will the lag reduce while in game? I can give addition specs for my comp if needed to help with answer.