Hi Anne, It wouldnt surprise me to hear of root rot problems. It could also be that the shrubs were old and on their way out anyway. Usually we do not recommend a fungicide without knowing the specific problem and associated fungus. If you choose to use a fungicide a copper product or one containing chlorothalonil are often used for root rots. I would recommend taking a long look at the dranage in the area and make sure gutters are emptying correctly. Also I would consider adding compost if the soil is high clay. Planting healthy plants and correcting the drainage is the key. I doubt you can out wait the fungus. evergreens generally do not like overly wet soil. Boxwood maybe. or Itea Check out this website very helpful in selecting plants.
http://www.bestplants.org/ good luck, Sandy