I have a Problem In Coding for Punbb Forums

i m Using: PunBB 1.3.5
i have a website with punbb forums software.

rezax123.com

i wanna show ads in some part of my forums. i mean only in the Adult Section category.

so i made a Category by the name "Adult Section".

now i tried 2 codes but no result:

1:

<?php
if ($cur_cat['id'] == '2')
<script type="text/javascript" language="javascript" charset="utf-8" src="http://adspaces.ero-advertising.com/adspace/127974.js"></script>;

2:

if ($cur_cat['cat_name'] == "Adult Section")
<script type="text/javascript" language="javascript" charset="utf-8" src="http://adspaces.ero-advertising.com/adspace/127974.js"></script>;

i even use echo and print before the <script> but yet no result.

i never use php before so i m confused. and i don't know how the punbb store name in database. can anyone help me?

where should i put the code for working it.