i've joked with my dh that a mean rooster is a tasty rooster. look for a Coq au vin recipe if you can. it's a way to stew an older bird but it was originally made with an old rooster as the main ingredient instead of the tender birds you can get at the local stores today.
If he's old he'll need to be stewed bc he'll be tough, but meaty. Go to backyardchickens.com (link below) and look up the Butchering and Evisceration Stickie. That's how I learned to butcher my birds. I use a tree and tie them up by their legs with baling twine, which I SWIM in after opening up 400 bales of hay/winter. I super sharpen my knife--a couple of years ago I bought a field dress kit for hunters--and I use safety gloves bc I've sliced myself before. I cut the "jugular" below the cheek and bleed mine out. They are gone is less than one minute and are unconscious in about 15 seconds. After it's a corpse I saw off the head. I usually butcher in multiples of two bc my dogs like the heads and the feet.
He's a vicious bird and needs a death sentence.