From what insomniaworks said in post #3, when he installed PERL, the path didn't get set properly (it's usually inconvenient to always run scripts from the install directory).
How to fix that permenantly requires editing the system PATH environment variable, detailed instructions for which depend on the Windows version being used.

The #! is a Unix / Linux thing which allows you to set the shell to be called to run the script, it's irrelevant on Windows as this line will get treated like any other comment.

To run a script without invoking the PERL interpreter directly on the command line the .pl extension needs to be correctly associated with perl.exe