slow graphics, need some help

Ok I have an HP Pavillion zv5201us running a celeron 2.8, with 790M of ram, ATI Mobility Radeon 9100 @128M, and a 60G hard drive. I have the latest drivers, and I am running Windows XP Home. The first time I ran it it ran smooth, but when I changed to the 747 @ LAX airport the graphics slowed way down. What settings can I adjust and in what directions do I adjust them. FS 2004 runs perfect on my desktop that is a less powerfull machine. I am sure this laptop can run it just as good I just don't know what to tweak.