the other two are right about the shock theory, although the drag racer has some hidden truth to the softer suspention set up. the soft srt up allows for the rear end of the vehicle to "drop" therefor allowing the center of gravity / weight distribution to be transfered farther back in the chassis, allowing for easier lift of the front end... the problem with softer shocks is that it absorbs the torque created by the sudden acceleration... (just a little information I've learned in advanced placement physics and automotive suspension theory in automotive technology) your best bet for pulling wheelies is to go to a shorter suspension set up in the rear, allowing for that weight transfer i was describing earlier, but the harder is better theory may not work as well as they think, with the harder shock set up you can also loose traction due to the tires breaking loose, so just lower the rear as far as you can without softening the shocks...
as for jumping, make sure you do not keep this same setup because you will most likely bottom out,.
*note to nitrotruckn sometimes an education can save you say 34 years of experience and come out with a little better results as well...J/K