It can help to use the large muscles in your arm rather than the smaller ones in your wrist and fingers. I double click without meaning to all the time. I also click as I move the mouse about the screen and have ended up on some very strange sites:eek

I have fingerless lycra computer gloves which are meant to help with joint pains and they actually give a lot of support. Only problem is they have a very thick seam which digs in so I have to wear them inside out - very glamorous!

One of the suggestions for MS tremors is to wear those wrist weights as they can damp down the movements, but I have never tried it. They say that it can mean the difference between drinking from a cup or having to use a straw so might help with a computer.

I hope something helps, the mouse setting is probably your best bet.

Alison