You guys are really giving this guy a lot of bad info. A new trackbar is not really needed on a 2" lift. I don't have one on my Rusty's 3" lift and the front axle is barely misaligned. I'm sure he can do without it for now. Also, different backspacing is not going to help his rubbing issue on the front and rear of the rear wheel opening. I bought my XJ with a small 3" lift and 32" tires and it rubbed in the same spots he is talking about, as well as the back edge of the front bumper.
Like he asked about in his 3rd post, trimming is the answer. I just removed all my flares and trimmed the fenders a bit and now any rubbing issue I had is completely gone. My tires are a bit too big for my lift, but a quick trim in the front and cut/fold in the rear opened up the wheel wells drastically. It'll make the jeep look more aggressive too. Keeping the stock backspacing or something close to it isn't a bad idea if he trims, because it'll keep the tires from sticking out too far without the flares. Still, there are writeups where people put the stock flares back after the trim, which is a possibility as well.
Still, if he really wants to change the backspacing on his rig, new wheels are definitely the way to go over wheel spacers. 3.75" backspacing is pretty aggressive and something like 4.5" or 4.25" might be a bit better. Plus, the spydertraxx spacers are over $100 a pair, and he can get cragar wheels for less than that, and they even fit his 31" tires.