Improving Gameplay

Sorry if this question has been answered before, tried a search but couldn't come up with a definate answer to this question.

When I play FM, my 3D and 2D are both laggy. Since I have only 1GB of RAM, and it's very cheap to buy RAM, I was wondering if another gig of RAM would improve my gameplay. I have done many other things to try to improve gameplay, including: not doing anything other than FM at that time, defragging, running CCleaner, turning off all visual effects for Vista, removing the vista sidebar, changing my laptop setting for high performance, and removing any programs I don't use. I even tried to set FM as high priority from the task manager. After all of that, the gameplay was better, but still lagging.

Also if there are any more ideas, I would be happy to try them!

Thanks for the help guys.