First, you are confusing "command prompt" (of which there is none involved here) and "console". There's a number of ways you could prevent the console from closing when the script terminates.

You could create a shortcut to your script and configuring the shortcut not to close the console on exit.

You could launch your script from another console application (e.g. the shell) that will continue to run after the Perl script exits.

You could create a shortcut to another console application that will run your script and continue to run after the Perl script exits. (e.g. cmd /k "perl script.pl" or cmd /c "perl script.pl & pause")

You could create an association to your script's extension that will run another console application that will run your script and continue to run after the Perl script exits. (e.g. cmd /k "perl script.pl" or cmd /c "perl script.pl & pause")

You could forgo exiting your script until the user wants to. (e.g. By using END { print "Press enter to exit\n"; <STDIN>; })

Just add the following to the end of your script so that it continues running until you have read the results:

print "Press <enter> to continue\n";
<STDIN>;
[download]

-Mouse

Update: Based on some of the things you say, I suspect you have an error in your script. Being able to read error messages is one of the advantages of my -Mouse.

For changing the colors of the text in the window, there are several options. You can configure the text colors if you make a shortcut to your script. Or, once you get the console window to stay open, if you don't have a shortcut, you can change the text colors and you will then be prompted if you'd like to apply these color choices to any future console windows with that same title (the title should match the script name).

For a better solution, see Re: Small Problem with running Perl Scripts in Windows.