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You should go with cracked section properties as Section 1910.11.1 of the UBC provides modified properties to be determine lateral story drift. If your lateral force resisting system includes a shearwall, here is what yo should do, determine if the tensile stresses in the shearwall are greater than the modulus of rupture (7.5 *sqrt f'c) of the concrete (these would be the S22 stresses if the local x axis is in line with the global x axis). If so then the section is cracked. Use a value of 0.7Ig for serviceability. For the same model, apply crack section properites to shearwalls(use 0.35Ig or whatever is agreed upon) for strength design as they would reflect a true redistribution of loads.