You could try this:

OptButton1_Enter()
OptButton1 = True
End Sub

OptButton2_Enter()
OptButton2 = True
End Sub

I have this code on one of my forms and it works fine. I do find it a
little annoying that the option I want to set doesn't stay if I have to tab
through all of the options. For example, if I start at OptButton1 and set it
true, then tab through OptButton2, I always have to go back and reset
OptButton1, then use the mouse or an accelerator key to avoid setting the
focus on OptButton2 in order to avoid setting it to true.

Good luck

Dave