You may find storing your settings in an XML file might be useful (for ease of putting data in and out). Yesterday I found a rather crude but adequete for the job class to extract data from an XML file. It can be found at:
http://www.phpclasses.org/browse.html/package/1398.html
In case you don't know XML here is a sample of what it could look like:
<?xml version="1.0"?>
<settings>
<name>administrator</name>
<email>admin@mydomain.com</email>
<user>Me</user>
<password>ghtyekdf</password>
</settings>
If you don't know what XML is then I would have a look at WebMonkey's tutorial here:
http://hotwired.lycos.com/webmonkey/98/41/index1a.html?tw=authoring
If you don't want to go down this route then you need to read some of the filesystem functions in the PHP (www.php.net) manual including :
file()
fwrite()
If you need more help post back/private message/email me for help.