Regarding fixing this thing yourself, I have one word for you. Ready? Here it is:
have shut everything down and have since been using a electric plug in the wall heater. I've called a repairman in to come over next week but since I found this awesome site I figured i'd ask the pros and see if I could fix this puppy myself.
By what you describe, you have some serious furnace issues that MANDATES an investigation by a qualified pro.
Building Physics Rule #1: Hot flows to cold.
Building Physics Rule #2: Higher air pressure moves toward lower air pressure
Building Physics Rule #3: Higher moisture concentration moves toward lower moisture concentration.