If your looking for a good on road tire that will get you pretty much anywhere you want to go offroad, I highly recommend the Goodyear MT/R's. You can get them in either the 35" or 37" size. I recommend the 37's. They handle and ride nicely on the road without a lot of noise, and they perform great offroad too. In my opinion, they give very good traction in the mud, and excellent traction in the rocks. They are also very durable and have a puncture resistant compound that allows them to be very durable in the rocks. This is what I am running right now, and will be my next set of tires too.
-Harrison