Un and re - installing has become an aerobic exercise.The 8800GTS - NVIDIA DRIVERS 96MB shows in ADD/REMOVE progams, in HKey_LOCAL_MACHINE\SOFTWARE\NVIDIA Corporation\Global in C:\NVIDIA\Display Driver\191.07 in C:\Program Files\NVIDIA Corporation in FS9.cfg - anything missing?
FS9 is attempting to do its thing.  It's a little slow getting to the first screen and, each time you select an item, progressively slower.  Watching it in 'Task Manager' shows it 'not responding' when an item is clicked then, after about 30 seconds returns to 'running' and a screen reluctantly shows up.  The ultimate problem is/are the low FPS.  Starts at 0 and, with AA off, goes as high as 13.  With AA on, 3 is the norm.  This is saying the graphics are apparently not reaching the game but the HOW and WHY are beyond me.  It's hell to be Stupid and Old  .

Hagar wrote on Oct 30^th, 2009 at 2:29pm:
Disabling Anti-Virus is one thing not tried yet.  This all seemed to start about the time I upgraded the diver but obviously not correctly.  If some kind soul with a similar graphics card (GeForce8800GTS), and nothing better to, went into their files/folders, comparing entries and found something I don't show, that might be the answer.

Hagar
Have had this little phenomenon happen twice now when uninstalling FS9 from disk one.  There's a remnant of the ...\Flight Simulator 9 folder which is ...\gauges.  This is the same problem that you and Shane G discussed about a week ago.  That time, simply reinstalling over the top of these files made that go away - just for a while apparently.  Perhaps my four disks have some corruption which could be cured by replacement?

Getting fairly familiar with the drill but this was something different, as the Pythons used to say.  After the uninstall from disk one, these few files were just arbitrarily left in position - the uninstall never got them.  A check around showed everything else gone.  Attempts to delete them were futile so, back to Google.  It seems XP has a propensity to refuse deletion of files for no rhyme or reason so someone created a little item "bootmovegone" and it works.  Unfortunately my problem remains so I'm about resigned to buying another copy of FS9 unless the Flight Sim Fairy comes to my rescue  .

Curiouser and curiouser... I can't say what's causing this, but before you buy another copy of FS9, do one more uninstall, then manually get rid of everything left behind. Don't trust the FS9 installer to do it right. I know that might seem illogical, but those four disks carry a lot of code, and the installer doesn't have much of its own. It's fallible.

But before you run the new install, get a different graphics card online- anything, even onboard mobo graphics- and disable the one you're using now.
If you don't have a "downgraded" video card handy to try this, I might have one you can borrow. It won't fix your problem, but it's a simple test that will narrow it down.

I don't suspect your card itself, but I think there's something goofy going on with the drivers. If you can get things running normally with some other card, you'll know for sure.

From there, you will have to deal with the nVidia software...ugh.  I have trod this path myself, and re-installed drivers several times. The last time was when I mysteriously lost my nVidia control panel functions... can't remember how I fixed that now, it's all a blur. It took a while, but I did it.
  I have no formula other than: when you get rid of something, make sure it's out of the registry; rule out hardware; install manually when possible. That, and: if at first you don't succeed... 

beaky wrote on Oct 31^st, 2009 at 12:26am:
This is something that's been lurking in the back of my mind so I'll install my old 8400 and see what happens.  What little test flying I've been able to do reveals FS9 trying its little heart out with just the onboard graphics - made several survivable landings at around 3FPS.  Runway's a little jiggly but hittable  .