You should be able to safely Resume your dailymail queue. In fact, I highly recommend that you do so that your subscribers don't miss any emails! When you resume a dailymail queue to completion you will receive the expected dailymail report.
There may be a problem with SMTP on your host. Are you able to send test messages to a test list and receive them at remote addresses?
Does your installation only send one or two hundred emails per day? If you've recently increased your subscriber base, mailings might be taking longer. Some servers have strict time limits on PHP script execution time, which can result in some messages remaining unsent and requiring a resume. The timeout is usually set at about 30 seconds, however, so I don't think you would have a problem with just a few hundred emails...
Regards