The name was confusing as changing it at runtime would not change the window to fullscreen, as it effectively only affects the start of the emulation.
Also blocked the ability to change it when the emulation is running, to be more inline with other similar settings, like "Render to main Window".
As in the comment, the panning was denaturalizing the volume (when the panning was at 0).
Unless users actually want to use panning, their wii mote volume should not be reduced, it should come out at the same volume the samples were.
If users want to reduce the volume of the wii mote speakers, they can do so from the wii home menu.
I opted for this instead of adding another setting "Enable Panning" as it would have been confusing, and the changes in the panning formula are unlikely to have any negative effect, as it still works.
Also added a IsRunning function as it was impossible to know whether it had been started or not (I will use it in later PRs but it should be there anyway)