To rule out programs causing conflicts with your game, you can use the following procedure to minimize the number of programs and services to the bare minimum.
1. Click Start.
2. Click Run.
3. Type MSCONFIG
4. Hit enter/click ok
5. When the system configuration window opens, go to the services tab.
6. On the services tab, click the "Hide All Microsoft Services" check box.
7. Click "Disable All".
8. Go to the Startup Tab.
9. Click "Disable All"
10. Click OK to save the changes.
Note that when you reboot, it will automatically run the MSCONFIG utility for you so you can undo the changes you just made, before you do that, run the program and see if your problem is solved.