[en] Elastic and inelastic, direct and exchange differential cross sections have been calculated for proton-hydrogen scattering in the energy range 250 eV <= Esub(lab) <2000 eV. The results are compared with recent experimental data and with other theoretical predictions. The impact-parameter approximation has been applied and the electronic wavefunction expanded into adiabatic electronic states. Both straight-line and Coulomb trajectories have been used to integrate the set of coupled equations. Furthermore the influence of the size of different molecular bases on the cross sections is studied and qualitatively explained in terms of the rotational couplings between the various Σ and PI states. Finally, integral cross sections for the 2psub(+-1), 2s, 2p₀ and 3psub(+-1) excitation are calculated in the range of 1 keV <= Esub(lab) <= 10 keV. (author)