If I understand correctly your setup is as follows:
4 radio buttons, as soon as you click one of them a different page needs to load.
You can simple do this client side, with JavaScript or jQuery, depending on your requirements.
Give your radio button an Id, and add an event handler for the 'changed' state, like this:
http://stackoverflow.com/a/8997289[
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You can then modify the JavaScript Window.Location property to let the user issue another page.
Optionally you can also supply parameters to the page (QueryStrings / URL rerouting) depending on your requirements.