So you need to email to a security group..

dsget group “CN=MySecurityGroupIneedToEmail,OU=Application,OU=Groups,DC=contoso,DC=com” -members -expand |dsget user -display

Or
as “CN=MySecurityGroupIneedToEmail,OU=Application,OU=Groups,DC=contoso,DC=com” is the GroupDN you can do this..

dsquery group -name MySecurityGroupIneedToEmail | dsget group -members -expand |dsget user -display

the display name column (except the first line) can then be pasted into the to box and resolved..