regular express problem

Hi

I am having problem in fixing the regular expression.
I want to forward all calls to shop.php but at the same time if[there is call i.e www.example.com then it should took it to index.php not the shop.php

here is my current expression, it always throw pages to shop.php even if want to go index.php it will take me to shop.pop

RewriteEngine on
RewriteRule ^/ index.php
RewriteRule ^([a-zA-Z0-9.]+) shop.php

Options +FollowSymlinks
RewriteEngine On
RewriteRule ^([a-zA-Z0-9-]+)/?$ /root/shop.php
RewriteRule !(css|js|png)$ /root/index.php [L]

RewriteEngine on
RewriteRule ^$ index.php [L]
RewriteRule ^([a-zA-Z0-9.]+) shop.php

regards