For those who responded to my earlier post, I think I have solved the problem I referred to, that is, parking brakes locked on, wild gyrations when attempting to slew, full up elevator etc. Someone said in another post that many problems are in setup, so I tried to find something in the setup that may cause the trouble. I ran the Logitech recalibration utility and noticed that it showed 2 joysticks, and when I disabled the joystick in FS9, one was still showing. Then the penny dropped. I have the Great Planes Radio Control Flight Simulator G3 installed which has a Futaba controller connected via a USB port, and FS9 was seeing it as a joystick. Apparently there was a conflict between the Logitech joystick and the Futaba controller, causing the strange behaviour.
When I first installed the GP Simulator there were no problems, but later I downloaded and installed updated drivers for the Logitech unit. This update was actually a reinstallation, and during the detection process, both units were detected and recognised by FS9, and subsequently caused the bizarre and very frustrating symptoms I described. I disconnected the Futaba controller, then uninstalled and reinstalled the Logitech joystick, and BINGO, all was back to normal. I just hope my hair grows back again - some hope!
I am posting this in case anyone else has a similar problem, so they won't have the frustration I did.
Again, thanks to all who tried to help, I really appreciate it, but as usual, the trouble was operator brain fade. However, in the end the lights came on and all is well - until the next time.