Here is an update on my FSX situation.
I removed FSX from my system and reinstalled it. I then installed the patch and have had no problems. FSX started right up and after adjusting the settings, I was off and flying. As reported elsewhere, the key is to install the service pack on a fresh installation and then reinstall any add-ons.
Without the performance tweaks I had before, I am getting around 6fps with decent graphics. I will play around with some settings and see if I can find that sweet spot. I might even throw a few tweaks back in and see how much more I can improve the frame rates.
Overall, I am extremely impressed with the improvements in FSX SP1. I will spend more time in it this weekend and possibly post some screen shots for you viewing pleasure.
After I work on that paper model a bit, I might look into upgrading my system and/or overclocking it.