All of em?
What tires you have(how well they grip), having lockers, choosing the right line, and just general smart about your driving is really going to be the major factors in deciding what you can and can't do.
Knowing your skill set, and knowing your Jeep's capability is the smartess thing I've learned to pay attention to.
Start small, by the time you get to the crazy hardcore rock crawling you'll be thankful you did because you took the time to learn it right.
And don't go alone.