Atomatically thin4He films of up to three monolayers on molecular hydrogen (1,1,1) surfaces are studied at T = 0.5 K, using path integral Monte Carlo. We compute the binding energy of4He to the H2 substrate as a function of4He coverage and obtain evidence of the prewetting transition. Density profiles perpendicular to the4He-H2 interface are obtained, as well as the zero point motion and effective mass of4He parallel to the substrate surface. The superfluid density of4He vs. coverage is calculated, and the intermediate scattering function is computed, from which we estimate the speed of third sound. Finally, we calculate the vorticity-vorticity correlation function.