1. the round thing in the center of your axle is the differential. A open diff will let the wheels spin at different speeds, which is good when you are driving around corners at any speed beyond a crawl. You want them locked in the rough stuff to make the wheels spin at the same speed, giving you better traction. (a open diff is really 2wd...1 front wheel and 1 rear window will be giving you the traction)
2. ATRAC is a computer controlled traction aid that will brake the spinning wheels and apply power to the gripping ones, giving you better forward momentum in the rough stuff.
3. bells and whistles are not necessary, but nice. Rocks will shred plastic bumpers if you wanna go hard core. 4 wheeling at night is not a good idea, but when you have to its nice to have extra lights. The other solution is to avoid those situations. Looks have something to do with it too, lets be honest.
4. No. More height is better for more extreme wheeling but it has disadvantages. IFS (FJCs) are harder and more expensive to lift and lifts strain drivetrain components, wearing them out faster and breaking things easier.
5. Move out west. 'nuff said
