I'm a huge fan of Schwalbe Marathon plus tires. I know, I know I should be recommending 26" tires and as I ride 700c I'm not actually qualified but I don't think the tire size has such a massive effect on comfort or durability etc (width does have a lot to do with comfort though)
The marathon plus is pretty much everything a tourer could want in my opinion. The only downside I see in them is the weight but considering this is touring it's really not that big of a deal. Really good puncture protection, one could probably say best in the market, good grip and deep profile so handles various conditions well. They are unbelievably uncomfortable when ridden unloaded and also a bit slow, but with a loaded bike they suddenly become seriously comfy and a lot faster.
Having said all that, I'm trying out a new system where I have the marathon plus in the rear and a lighter more supple tire up front (in his case vittoria Voyager hyper, the former randonneur hyper). This way I can balance the needs the different ends have. Front needs grip, suppleness and speed while rear needs durability, puncture protection and weight bearing capacity. Using different suppleness levels in the two ends will also probably protect the wheels a bit better (mainly the front) as they receive the 'suspension' more appropriate for their needs.
So as a recommendation
Rear: Marathon plus and since it's 26" in 41mm+ width
Front: A ligher marathon tire like the supreme or green guard, or a Grand Bois for example.