What is your current brake situation? Disc from and drum rear, all drum, or all disc?
My 2002 Wrangler was fitted OEM with disc front and drum rear. Looking at the pad and disc wear over time, it was clear that the front brakes were doing most of the braking work. Sure, this is to be expected, but it seemed to be more than the 60/40 one would expect.
Anyway, going to larger tires seemed to be the cause. So I went with an aftermarket slotted rotor and performance pads, and that seemed to improve braking performance. I looked into disc conversions for the rear, but in reading up on them, it seemed like many reviews were suggesting the performance improvement was pretty nominal.
I believe this was the pads and rotors I ended up using:
Crown Automotive RT31012 Performance Front Disc Brake Service Kit for 99-06 Jeep Wrangler TJ and 99-01 Cherokee XJ | Quadratec