I'm sorry you're having trouble. I've had one similar report so far and I have no idea why this happens on some systems. I'm running it fine with Intel HD Graphics, so I don't think that's the issue.
What's your screen resolution? The game runs in 1024x768 and defaults to windowed mode as long as your screen supports it (width must exceed 1024 and height must exceed 768). Fullscreen will be forced to "on" otherwise.