No Air / Center Front Vents & Rear Vents

[tilley]

I did numerous searches so I apologize if this is a repeat. I couldn't find anyone experiencing my exact problem(s).

Windshield and Left / Right side front vents seem to blow air adequately (i.e., heat), but both center front vents nothing. Rear seat vents also nothing, however when I select the Rear A/C button and turn the rear knob to HOT, I can 'feel' the slight vibration of what feels like a blower spooling up (I feel it in the drivers seat, through the floor). It takes about 20 seconds or so before I feel it, but still no air comes out.

Am I experiencing two separate problems here? I read about the rear resistor/thermal fuse issues, and checked the famous $1 screw near the firewall, but couldn't find anything about the front center air problem.