Figuring out battery life from amp draw?
0.7 means 0.7 amps! (i.e. 700mA).  I would be very worried if it was drawing 7 amps :) 

You are nearly there with your calculation though: with two AA batteries in series, the total capacity is still 1800mAh. If you had it in parallel, then it would be 3600mAh (but batteries in parallel is not a good idea in general, the exception being lead acid batteris and similar, under certain conditions). So 0.7 amps with 1800mAh capacity means it would last 1.8/0.7 = 2.57 hours (2 hours and 34 minutes)