Can I temporarily suspend my email account and, if so, how?

I recently had my computer hacked and the lovely person who did this has been using my att email address all over the web to create bogus accounts on many, many web sites across the net. I'd like to temporarily suspend the account with the hope that a mailer daemon will get generated back to the sites that have gotten scammed by this individual. So, can I temporarily suspend my email account and, if so, how do I do it and will a mailer daemon get generated back to the sending web site to let them know the message was undeliverable?