Thanks for those config suggestions Alpha, appreciate it, I'll give them a try!
As far as the mouse problem goes I have tried clicking on the desktop icon to launch, and then not moving the mouse until the game is up and running. Yet still the mouse is frozen until I reduce to desktop and then launch again. Have also tried clicking on the game launch within Windows folder, same problem. Even when I had the old ball mouse I had this problem. In fact as far as I can remember I've always had this problem.
Interesting tos ee that it affects some and not others. A real random thing. I guess I've lived with it all these years, a few more won't hurt!
But thanks to all for the suggestions.