Assuming you have your Radio Button as following:
<RadioButtonGroup Property="SOME_PROPERTY">
<RadioButton Value="0" Text="disable / hide labels" />
<RadioButton Value="1" Text="enable / show labels" />
</RadioButtonGroup>
you can control visibility or availablility of other elements in the dialog by using Condition
sub-element:
<Control Id="SomeLabel" Type="Text" Text="text:">
<Condition Action="disable"><![CDATA[SOME_PROPERTY <> "1"]]></Condition>
<Condition Action="enable"><![CDATA[SOME_PROPERTY = "1"]]></Condition>
</Control>
<Control Id="SomeLabel2" Type="Text" Text="text2:">
<Condition Action="hide">SOME_PROPERTY = "0"></Condition>
<Condition Action="show">SOME_PROPERTY = "1"></Condition>
</Control>
Following the request in comments, posting an example of updating property with values of Edit elements (some required control attributes are ommited for clarity):
<CustomAction Id="CA_SET_TO_A" Property="P" Value="[AA]" />
<CustomAction Id="CA_SET_TO_B" Property="P" Value="[BB]" />
<Dialog Id="MyDialog" Title="[ProductName] Setup">
<Control Id="Next" Type="PushButton" Default="yes" Text="!(loc.WixUINext)">
<Publish Event="DoAction" Value="CA_SET_TO_A">R="USE_A"</Publish>
<Publish Event="DoAction" Value="CA_SET_TO_B">R="USE_B"</Publish>
</Control>
<Control Id="MyRadioButton" Type="RadioButtonGroup" Property="R">
<RadioButtonGroup Property="R">
<RadioButton Value="USE_A" Text="Save text field 1" />
<RadioButton Value="USE_B" Text="Save text field 2" />
</RadioButtonGroup>
</Control>
<Control Id="A" Type="Edit" Property="AA" Text="{64}">
<Condition Action="disable">R="USE_B"</Condition>
<Condition Action="enable">R="USE_A"</Condition>
</Control>
<Control Id="B" Type="Edit" Property="BB" Text="{64}">
<Condition Action="disable">R="USE_A"</Condition>
<Condition Action="enable">R="USE_B"</Condition>
</Control>
</Dialog>