Contracted Gaussian basis sets plus polarization functions generated from the improved generator coordinate Hartree-Fock (HF) method were used to calculate, at the HF level, total energies and, at the HF and MP2 levels, geometrical parameters, harmonic vibrational frequencies, and electric dipole moments of a set of small molecules (ground states) containing elements of the first- and second-row. The results were compared with the corresponding ones calculated with the 6-311G^** basis sets. In general, our results are in good agreement with the experimental values.