here is a copy-paste dealio and i recommend it.
i used to eat the meat after it had been cooked along with the bones...big mistake. don't do that. and don't learn the hard way.
i recommend browning the bones first and then pulling what meat you can off, then proceeding from there.
regarding marrow...you can either eat it or boil it. either way, you will be getting good stuff. i found it really adds to the broth, but you can experiment. looks like you have a lot to work with! enjoy!
Mineral–Rich Bone Broth
Use bones leftover from cooked chicken, turkey, etc. or from whole chicken, pig's feet or hocks, beef bones, etc. Chicken feet are particularly rich in gelatin so they can be added to the pot or used to make broth all by themselves, or use bones with meat attached.
Acidic medium, i.e. unpasteurized unfiltered apple cider vinegar or freshly squeezed lemon juice.
Preparation Before Cooking
Poultry: Use about 2 to 3 pounds of bony parts, chicken feet, or 1 medium-sized whole chicken. Cut up whole chicken into several smaller pieces. Put them into a pot large enough to cover them with water by 2 inches (leave at least 1 inch from the top of the pot because the volume expands somewhat during cooking).
For every 4 quarts of water add 2 tablespoons of acidic medium, i.e. unpasteurized unfiltered apple cider vinegar or freshly squeezed lemon juice.
Let it stand for 30 minutes to 1 hour.
Beef, Lamb, Pork or Venison: Use about 4 pounds of bones with or without meat. Brown the meaty bones first, and add them, along with fats and juices from browning, into a pot large enough to cover them with water by 2 inches (leave at least 1 inch from the top of the pot because the volume expands somewhat during cooking).
For every 4 quarts of water add 1/2 cup of acidic medium, i.e. unpasteurized unfiltered apple cider vinegar or freshly squeezed lemon juice.
Let it stand 1 hour.
Bring the meat and bones to a boil.
Reduce heat to medium–low, and simmer, covered, until the meat attached to the bones is cooked.
Skim off any foam that rises to the top, which are impurities.
When the meat is fully cooked remove it from the bones, to be used in sandwiches or other dishes or added back into the bone broth after it is done. Put the bones back into the water and continue simmering – see cooking times for the different kinds of bones below.
Let it cool slightly, and remove any big bones with a large slotted spoon.
Strain the remaining liquid and store until needed in the refrigerator. If you do not plan to use it within 3 days it can be transferred to covered glass containers and put in the freezer.
NOTE: The longer the cooking time the more minerals are pulled out of the bones. The bones may even become quite soft which are healthy to chew on. Bone marrow from inside the bones is also healthy. Eating pig skin is healthy too, which can be made into cracklings (crispy pork rinds).
Chicken: Reduce heat and simmer covered for 6 to 24 hours.
Beef, Lamb, Pork, & Venison: Reduce heat and simmer covered for 12 to 72 hours.