The real issue with off-roading is understanding your limits. It is easy to get any 4x4 stuck. It is easier to damage any 4x4 on rocks, and tree branches.
I have been off-roading for a relatively long time. I have spent time with Rod Hall in Reno learning from him. I have spent so many hours off-road with two and four wheels that I think I now have a feel for not only how to go, but more important how to get out of the forest/desert.
My advise for newbys is to take your time. Pick your lines carefully. Know exactly where each wheel will track. Crossing logs and even small tree branches offers the potential for one end to rise and damage the underside of the vehicle. 4Runner seems to have well protected brake lines (including the emergency brake), other rigs I have seen do not do nearly the same.
The electronic goodies on the 4Runner make up for a lot of the know how I have had to employ in the past. But one should not rely on the notion that if you can get into a gnarly area that you can get out.
Take your time. Tread lightly. Take a GPS and lots of maps. Prepare for the worst with tow ropes, off-road jack, shovel, and water if you are in a burn warning area. Some of the best times I have had are being by myself in the middle of nowhere.
I posted earlier three photos of my rental 4Runner in the Ozarks. If you want to see what I was doing there you can look at the photos some of the riders at my annual event sent me:
http://www.dualsportmagazine.com/2003FCT.html