Suggestions needed to get peak performance

I would appreciate any help I could get on my system.
I am no computer expert but this is what I have.
Pentium 4 CPU, 3.2 GHz overclocked to 3.5 GHz
1Gig of Ram
Nvidia Geforce 6800 GT 256MB video card
80Gig HD
I have all the sliders maxed out on FS2004 and I have the frame rates set at 24fps. The frame rates stay up around 20 or better in most locations but when I get close to an airport such as Anchorage or Seattle it pauses for a second or 2 all the time to reload I guess. I have extra scenery in this spots. A place like LAX, with the default scenery, does the same thing.
Anyone have any ideas where I should be adjusting my settings in my video card and anything else that needs adjustments to stop the jerks and make it run better?
Pickup
I am no computer expert but this is what I have.
Pentium 4 CPU, 3.2 GHz overclocked to 3.5 GHz
1Gig of Ram
Nvidia Geforce 6800 GT 256MB video card
80Gig HD
I have all the sliders maxed out on FS2004 and I have the frame rates set at 24fps. The frame rates stay up around 20 or better in most locations but when I get close to an airport such as Anchorage or Seattle it pauses for a second or 2 all the time to reload I guess. I have extra scenery in this spots. A place like LAX, with the default scenery, does the same thing.
Anyone have any ideas where I should be adjusting my settings in my video card and anything else that needs adjustments to stop the jerks and make it run better?
Pickup