well, first off check out this Wiki Article. That will help some I suspect.
Your first problem is that just putting a file called cron in your home direcotry won't do anything. You'll need to type "crontab -e" to edit your crontab, or you could use "crontab filename" -replacing filename with an actual text file, to import that file as your crontab (and overwrite anything already there). If you're editing the crontab then once you're done you're press ctrl-o to save the file and ctrl-x to exit. After either command is carried out you will (hopefully) get a success message about the new crontab being installed, or an error message.
Next, I don't think that you really want your script to run that often... I'm not actually sure how often it will run they way you have have it set up, but it's a lot. I tested to see if that was even a valid setting, and it was accecpted, but... Read the wiki article to understand how specifying the time works, and decided how often you really want it to run.