instead of your random number to select gender code, try this:
PHP Code:
<form id="form1" name="form1" method="post" action="">
<p>
<label>
Male:</label>
<label>
<input type="radio" name="Genderselect" value="male" id="Genderselect_0" />
</label>
<br />
<label>
Female:</label>
<label>
<input type="radio" name="Genderselect" value="female" id="Genderselect_1" />
</label>
<br />
</p>
</form>
$gender = $_GET[genderselect];