The house that I am in has been constructed as a brick home and has ductwork that goes to areas that are 'outside' the "basement" area. (There is five foot area beyond the basement that has been 'blocked in' and is part of the furnace return air system and hes a dirt floor in it) My concern is how do I route the return air and make sure I am NOT being exposed to Radon Gases. The area is loaded with cobwebs.
The house is located in Canton, Ohio

First, radon gas testing is not very expensive, so you might test to see if there is a radon issue before you try to cure it.

If there is space, you might place 6-mil polyethylene film over the floor of the blocked-out space, and tape it to all walls and to any other penetrations. This will inhibit the entry of radon gas, and relieve any musty smells that might emanate from that area.

Another, more expensive, alternative would be to duct the return air from wherever it enters that blocked-out space to your equipment room. This could be very difficult to get a good air-tight connection to the structure above the space.

The polyethylene film will solve all your problems except the cobwebs.