A 265/70/17 will fit on the 7" rim..
The increase in dia will have only a very slight affect on gearing ( but may make your speedo actually read a lot closer to actual speed )
As for an allround A/T tyre.......really can't go past BFG A/T.....
Compared to the Cooper ATR and MT ATZ I had on previously, the BFG's are quiet on the road, safe in the wet, and are pretty good offroad as well..