The temperature dependencies of the rate coefficients, alpha(e), for electron-ion dissociative recombination (DR) of N2H+/N2D+ and HCO+/DCO+ ions with electrons have been measured over the range 100-500 K. Also, optical emissions have been detected at similar to 100 K from the N-2(B3 Pi(g)) electronically excited products of N2H+/ N2D+ recombination. The measurements were carried out using the classic FALP technique combined with an optical monochromator. For N2H+, there was no variation of alpha(e) with temperature above 200 K, with an average value of alpha(e)(N2H+) = 2.8 x 10(-7) cm(3) s(-1). The temperature variation for T similar to 100-300 K observed for alpha(e)(HCO+) is similar to that of N2H+ ions for T similar to 300-500 K. The smaller rate coefficient measured for DCO+ and N2D+ ions shows the influence of an isotope effect. The substantial enhancement of the vibrational level, nu' = 6, from the N2B state for N2H+ recombination over N2D+ recombination is consistent with previous result at 300 K and implies the influence of a tunneling mechanism of DR.