Ummm.... I never leave ports in the default VLAN, even if they are untagged. IMHO, using the default VLAN is poor practice *unless* the switch is being used as a private switch and not switching/routing any traffic off of the device.
WRT to your question: tagged ports will be reported as 802.1Q Tag = . Untagged ports are reported as "Internal Tag = "
WRT to your last question about a better method of showing which vlans are tagged/untagged on a single port: Try "show port vid"
Slot-1 b50ee2-1a-13.8 # show ports 1:53 vid
Untagged
Port /Tagged VID(s)
-------- -------- ------------------------------------------------------------
1:53 Untagged None
Tagged 2240, 2241, 2242
Slot-1 b50ee2-1a-13.9 #