For running internet radio:... try the documents at [http://www.shoutcast.com
], near the top of the page: "Wanna be a broadcaster? It's Free! Check the online docs to get started! "
I've never tried it.
For the webserver:
Check if you are actually running apache [just because it is installed doesn't mean it will start when you boot], open a browser window and try [http://localhost
]. It should bring up a page congratulating you on installing apache. If it says 'Connection Refused' then you need to use one of Mandrakes tools to start apache [sometimes called httpd] when you boot.
The files that apache servers are normally found in '/var/www/' webpages are in a folder called 'htdocs' or 'html', and perl scripts should go in 'cgi-bin'.
Apache should handle perl straight out of the box... as long as the files contained a correct shebang, and are executable. There may be something in the config file to turn it on... I can't remember. [Read: /etc/apache/httpd.conf or /etc/apache.conf, perhaps /etc/httpd.conf]