Hell BigBubar,
Before you start the game, make sure you dont have any unnecessary programs running in the background, these will use up system resource's, go to the task manager and turn off anything you dont use to play the game, dont worry about turning off anything vital, a simple reboot will fix it, experiment with what you need and what you dont need.
Also try a system defrag, you would be surprised at the effect this will have.
A cheap and effective way to give your system a boost. Post your results and good luck.