Nice rig. I have had an R51 for about 2 years know. Its been a great vehicle. I use my Jeep LJ Rubicon on trips that I plan extensive rock crawling. But if I am planning a trip that I want comfort and just forest service roads or easier trails the Pathfinder is much more comfortable. As you have found, there is some great drool material over at thenissanpath.
As far as tires, I will be putting on new tires on my R51 in the next couple of weeks. I decided on the Cooper ATW. Its basically the AT3 with more siping for better winter traction. I also considered Hankook ATM, Duratrac, General Grabber and Toyo ATII. I choose the coopers because they have the mountain snowflake winter rating and looking at the siping they are obviously built with winter roads in mind. I choose them over the Duratrac because I thought they would be quieter.
As far as tire size, I went with the 255/70R17. Slightly narrower than my stock tire and 3/4 an inch taller. If you are putting on a lift, I would really consider looking into a 255/75R17. This is a great sized tall and skinny tire. It will be about a 1/2" taller than the 265 you are looking at and about a 1/2" narrower. Thats about 1 1/2" taller than stock. Because its narrower it will likely fit better. Its the stock tire on the Jeep JK Rubicon. If you look around you can often find sales on the BFG MT in this size at ridiculously low prices. A couple months ago Quadratech had them on sale for around $100. Thats for a load range C. That is not the norm, but it does happen every so often. There are also Jeep take offs all over the place too as the Jeepers move up to 35" tires.
If I didn't have the Jeep and this was my only offroad vehicle, I would run the Duratrac in a 255/75R17 and never look back. Your needs might be different but I would seriously look into this size. I think you will be glad you did.
Edit: Right now tirerack has the BFG MT in that 255/75R17 size available for $134. Thats a great price on a great tire.