[pursuivant]

What to do in the arming (Gun Convergence)
and what do this setting???cannon/machine gun/rocket/rockets delay/bomb delay????

If you have wing-mounted guns, or other guns which aren't mounted so they shoot directly ahead, gun convergence is the point where the shots from all your guns hit approximately the same point, essentially the point of a "V" or cone. Your guns are most effective if you shoot at the range where their shots are set to converge. If you have them, you can set your machine guns and cannons to converge at different ranges, since cannons generally have shorter useful range than MG. Typical convergence ranges are 200-300 meters, although for lightly-armed, extremely maneuverable planes (e.g., the A5M), I've found it's more effective to set gun convergence to 50-100 yards. Skilled shooters sometimes set convergence for 500+ meters, but shooting at such long ranges is usually a waste of ammo.

Rocket/Bomb delay is just the time in seconds before the rockets/bombs explode. Rocket time delay generally doesn't matter unless you are using air-to-air rockets. Then you want a delay of no more than 8 seconds or so; otherwise they drop too far before they explode. Bomb delay is very important if you're doing low-level bombing runs - you want a delay of 2-3 seconds to avoid getting caught in the bomb blast. You can get away with a slightly longer delay if you're hunting ships. For moving armored vehicles, anything more than a couple of seconds of delay gives the vehicle time to move out of the bomb blast area.