Windows crashing on start-up (Steam)?

Recently, I downloaded Steam for my dual-booted Mac. I was playing a free game, America's Army 3, and when I entered the first game, a blue circle filled the center of the screen, and the game froze. When I went to restart the computer (using Windows Partition), it would go to a dark gray screen, and it sounded like nothing was running, such as fan or processor. Next time, I was given the option to run start up repair, and it says "Windows is locating files", the bar graph fills, then it goes to the same blank screen. Fortunately, I can access my windows hard drive using my mac, so if needed, I can delete certain/all files ociated with Steam. If you can help, please add detailed instructions. I am good with computers, but not good enough to really fill in the blanks when my hard drive is on the line.