There are two different rotors for the Jeep Wrangler. Measure your wheel studs, should be either 1 1/2" or 1 1/8" long. Make sure you get the rotors that go with the length of the studs. If you get the wrong rotors they will fit but the wheels will lock up when you tighten the lug nuts.
yes
Inspect your calipers make sure pistons are working
no, just the wheels the brakes apply to, usually the front brakes
Rear drum brakes, that lock up during heartbreaking quicker than the front brakes, can be adjusted. The rear brake pads need to be backed off.
yes, the only purpose of the anti-lock system is to keep the wheels from locking up when you slam on the brakes. The brakes them selves function as usual. You will just have the chance of locking your wheels up and sliding if you slam on them.
does you truck have drum brakes in the back
In a car without ABS, if you slam on the brakes, your wheels will lock and your car will skid. ABS prevents the wheels from locking by releasing the brakes if you start to loose traction.
The actuator on the front differential may not be engaging to lock in the front axle. How can I fix it?
Disc brakes in the front, drum brakes in the rear. Anti-lock brakes were optional.
If it doesn't have manually locking hubs on the front wheels, It means it's a "constantly" locked front 4x4. You don't have to lock them, they already are.
You or someone has refitted something incorrectly. Go over all your assmbly steps again.
if you slam on the brakes hard then the wheels dont lock up