Points to consider:
1. Try not to take form letters as an insult. The average publisher/agent has to deal with hundreds of manuscripts, and doesn’t have time to write individual notes to all of them, so don’t take it personally.
2. If you sent something that just took "the entire weekend", you’re lucky to get a form letter.
3. Threats of grevious bodily harm and death are not a good idea. You might end up talking to the police.