To the radio buttons works correctly, you must to have grouped by his name. (Ex. name="type")
<fieldset>
<legend>Please select one of the following</legend>
<input type="radio" name="type" id="track" value="track" /><label for="track">Track Submission</label><br />
<input type="radio" name="type" id="event" value="event" /><label for="event">Events and Artist booking</label><br />
<input type="radio" name="type" id="message" value="message" /><label for="message">Message us</label><br />
It will returns the value of the radio button checked (Ex. track | event | message)