OT and DNS advised you quite well as far as making sure the critter is done for. I am assuming you are bow hunting since your last post kinda hinted at that
... Go for the lungs. Largest target area as well as the easiest to get through. They go down plenty quickly enough with a good double lung pass through..
As far as eating size, on a good sow you are looking at anything from 60 pounds up to around 150-170 will have some really fine eating meat. Pretty much the same for a good boar. Anything over that, the back straps will still be fairly good but everything else will be pretty much sausage meat in my opinion. Of course that is also dependent on their feed as well. Unlike beef, pork doesn't necessarily have to be hung and aged all that much. 2-4 days is all it really needs for aging in my opinion and since I don't have a scalder pot I skin mine out as fast as humanly possible and quarter it out and get it in the cooler. I have racks set up in my coolers to keep the meat off the bottom and out of the water and blood. Works just as well as hanging it in my walk in cooler.