As for eating them, avoid large males. They stink, their meat stinks. Perfect ideal size is 80-120 pounds of either sex or less than 200 pound male. I have made delicious sausage of a very large (450+ sow). I would avoid large boars for food but you should have no trouble eating the others.
As for cleaning them, well, their hide is very tough. Skinning them is not exactly fun, but is doable.
After many years of dulling hunting and pocket knives I found this secret.
Utility knifes - with good disposable blades. I really like these titanium ones, they hold up well. And when your done, you throw them away and do not have to sharpen anything. They make cleaning these things much easier. Go to amazon and read the reviews on a search for "lexon titanium blades". They fit into any regular utility knife like a stanley or the like.
.. second, after skinned, I use a dewalt cordless sawsall to remove my roasts at the joints and remove the feet. Sometimes I can go from live pig to dead pig to 2 shoulders and 2 hams in the cooler on ice in under 10 minutes. I'v never brought the ribs home because they go on the smoker at camp.