How do you change the stills function from 4.3 to 16.9 its really not very clear?

Hi
Having looked at the full manual - downloaded from here and savable:
http://tda.panasonic-europe-service.com/docs/2z54662404z3z38916z656ez706466z22zdf06e277f71e6367f9e09db70241478cb0ad23ae/tsn3/data/ALL/HXWA30EG/OI/902781/vqt4x32.pdf
I think you will find that you cannot actually change from 4:3 to 16:9 aspect ratio for a particular pixel sized picture. When you set the pixels for the picture you want, the aspect ratio is set automatically.
For example:
16Megapixels 4608x3456 4:3
12Megapixels 4608x2592 16:9
See page 96 of the manual mentioned above for a full table of Megapixels, size, ratio etc
Therefore changing the picture size from the simple menu changes the aspect ratio but you do not have control of the aspect ratio for each size, in other words you cannot take a 16Megapixel picture at 16:9, it has to be 4:3.
Hope this has been helpful
Cheers