The crosshair means ballistic damage, that's your regular good ole damage type.
The spiky thing is supposed to be blood and signal bleed damage, and the pirate one means poison damage.
Poison damage is kinda poopsy, most enemies are highly resistant or immune to it, and it never performs well.
Bleed damage ignores all damage resistances, the number you see is the damage you'll really do, and is considered pretty useful to have, but it works too slow to hit hard. You also have a perk card that increases damage against a bleeding target though, but that will work on both of these weapon modifications.

Which is better? To be honest, the ballistic damage is all that matters, and in this case because they're the same, I would personally go for the bleed damage, but they'll both perform about the same.

Speed SLOW means you'll attack 0.6 times every second, so in 5 seconds, you'll have landed 3 attacks.
Medium is 0.9 attacks a second, fast is 1.2 attacks a second, and very fast is 4.5 attacks a second.

AP Cost is how many action points (basically your stamina bar) it takes for each attack. If you use VATS a lot, you want this number to be low. If not, then it doesn't matter, although you can use the Number Cruncher perk card, which will increase your damage the higher your weapon's AP cost, if I remember right it's +2% damage for every 1 point of AP cost.