JIRA Defaults
The "JIRA Defaults" tab allows you configure the default issue type, priority and status when new JIRA issues are created. You can configure the defaults to "Warn and require manual entry" however if you do this, you will be required to manually pick these settings from the JIRA Issue Info dialog before the task will be used to create a new JIRA issue.
The drop-down boxes provide a list of all the current configured settings in JIRA. If you add a custom issue type to JIRA, this issue type will be available for selection in the drop-down.
NOTE: JIRA projects can have different issue types available under each project. The list on this configuration screen shows all of the issues setup in JIRA. So even though you may have an issue type as an option, it may not be valid in JIRA and may cause errors when creating and/or syncing.