Assuming you are talking about new bikes (you didn't post any information about the bikes except for wheel and tire size), get the one with 700/38c because:
a) this is a good tire size for type of riding you are describing - 2.3 inch is just unnecessary (and will probably be some kind of MTB tires);
b) 26 inch wheel size is obsolete and pretty much dead - it was popular before but nowadays it is pretty mostly reserved to the lowest end of the low end bikes, it is becoming more and more difficult to find decent tires for 26 inch wheels.