Depends on what else they are doing. In general, if it is only a bite and two claws, then the bite is at normal BAB+Strength and +Strength for damage while the claws are secondary natural attacks at BAB+Strength-5 and +half Strength.
If you have a weapon and full attack, then the weapon is at normal to hit/damage but the bite and one claw (since the other is holding the weapon) is at -5 to hit and half strength. Obviously if you have a two handed weapon, then you only get the bite and it is still at -5, half strength.
A monk with natural attacks does not use the natural weapons when they flurry UNLESS they have a feat Feral Combat Training. This allows a monk to use one natural attack's damage IN PLACE OF the normal unarmed damage rolls. You pick the particular natural attack to use when you pick the feat.
It depends. Some creatures use claws as primary and some don't. I looked up hybrid werewolf forms and they do appear to treat claws as primary, so in this case you would do it as primary too. Unless, as I said, you also are attacking with a weapon, at which point all natural attacks made in a full attack would be considered secondary.
You don't have to use your hands for unarmed strikes. If you use unarmed strikes with natural attacks your natural attacks become secondary attacks at -5 to hit and half damage str bonus to damage. If you have multiattack and it becomes -2 to hit.
If you are a 14th level witchwolf monk and you have 18 Str, 10 BAB and multiattack with no other feats your attacks would look like this:
Unarmed Strike +14/9 2d6+4, Bite +12 1d6+2, 2 Claws +12 1d4+2
OR
Flurry of Blows
+16/16/11/6 2d6 + 4
Hope that clears things up.