First of all: it's great that you put effort in making the lives of disabled people better

awesome.
I dont think it'll quite work if you place a dot on a persons forehead, since the movement wont be that big. I'd go for placing the wiimote on a helmet, or something, and then have a sensor bar on top of a screen. For making clicks work i saw a pretty cool approach on television some time ago. They did it with eye-tracking, which is completely different, but what they did was something like this: If the cursor was at 1 spot for more than 2 seconds, there would be a mouseclick. I dont know what they did with the right clicks though.
Anyway, keep up the good work;)