Flashing / Hesitating Screen

I just installed FSX.SE, i had issues with addons but have resolved the problem(s), i now and have had issues with screen flashing and hesitating from the beginning i have re-installed FSX.SE five times thinking it would help no luck......these are the things i have noticed, every time i use my mouse (Synaptics Pointing Device) or external mouse (Corsiar) in the cockpit to do anything from altitude,speed,course change ect. when i use the left mouse button that seems to activate the flashing ect, (after 10-15 secs) it settles the more i use that button the longer the issue will last, when i use my right mouse button i can do anything from altitude adjustment from 100 ft to 30000 ft with no issues even if i clicked the mouse fast, i also see the (NOT RESPONDING) flashing next to the FSX logo on the top left of the screen, also the FSX logo in the taskbar will flash and move (slide) to the right and the will move (slide) back when flashing stops, when using the joystick say to activate auto pilot i see the little finger on the hand move (like giving me the finger) not sure if that is relevant.
I would appreciate any help in this matter as i would like to get flying again.
Thank you in advance.
Cheers Terry.