Because you have used your Y and Z axis you are a little cornered. One option would be to add some text boxes which change as you click on each option button. I have attached an example though with the table in play I am not sure of the value of adding this information to the chart.
I had a look at your coding and it seems overly complex. You can simplify it to the following.
Code:
Private Sub OptionButton1_Click()
[B5:B14] = 1: [E5:E14].NumberFormat = "0.0%"
End Sub
Private Sub OptionButton2_Click()
[B5:B14] = 0: [E5:E14].NumberFormat = "0,000"
End Sub