Dillon-I never use any aircraft until I convert the exterior daytime textures (they are the ones that end with a _T.bmp) to DXT3 or DXT5 and they are mip-mapped.  You can use DXTbmp or Imagetool to convert the .bmp's

Also running a good defragmenting program like Ultimate Defrag once your HD gets to be more than 6% fragmented is a good thing to do.  You should take all of your addons and place them onto removable media. The less clutter you have on your HD the better FS9 will run.

You should look at installing nHancer for your nVidia card.

Rob