You will want to follow the upgrade instructions.. Which go something like this.

1.  BACKUP EVERYTHING.  (I cannot stress the importance of this enough!)
2.  Make a backup copy of your current web.config file
3.  Place an app_offline.htm file on your production DNN site (This will prevent users from accidentally triggering an update
4.  Unzip all DNN 4.4.1 upgrade files over your existing file information.
5.  Rename release.config to web.config
6.  Copy your existing connection string, validation key, and decryption keys from your web.config backup to the new web.config
7.  Remove the app_offline.htm file
8.  Navigate to <url>\install\install.aspx to start the upgrade
9.  You should see an upgrade successful message.

This SHOULD be the correct steps, however I am reciting this from memory please double check with the DNN documentation.  I will also be posting a step by step guide to this on my blog in the near future.