This is right about the same as Wheelin's recommendation, however some reasoning behind my setup as well...
I live where it gets crappy in the winter and its not really that bad, but there are so many people that suck at driving. Not to mention there are just a ton of cars on the road out here in the Chicago suburbs. So, to retain my ability to drive on snow/slush/ice covered roads, I went with a true-trac out back and while I have not done so yet, it is my intention of getting a selectable locker for the front (ARB for me).
Search for Lupinsea and click on his Jeep Mod Reviews link in his signature. He has true-tracs front and rear and I think he is pretty happy with his setup, he has a review at the very bottom of the page the link sends you to.
Red Jeep Club Member 111
'99 TJ - work in progress...see profile
'08 WK - Silver RME, DD.