ok, this is pretty simple.
first check to see if PHP is installed on the server your site is located in. a simple question to the admin would do the trick. to be honest most servers that host have php installed. then to check if php really works where your website is located, create a file info.php inside it to make sure php is installed incase the admin take long time to reply back to you.
<html>
<head>
<title> PHP Test Script </title>
</head>
<body>
<?php
phpinfo( );
?>
</body>
</html>
Afterwards, open your browser and type in the address to view that page. Something like... http://www.yourdomain.com/info.php
phpinfo is one of the "built-in" functions that PHP does. There are many others, but this one is a nice one to use to start of as a test.
Ok this being done. then you simply follow the installation instructions given to you by minishowcase. Dont worry its not as hard as it seems. php is a very friendly programming language which is why many people use it. so just give it a go. if you need help setting minishowcase up even after having a go at following the instructions then just give me a shout.
Although you have enough information here to get on with it :D
If you need any more help do let me know.
PK