The collective properties of system of surface electrons on a film of superfluid4He paired with substrate holes is discussed. The case when size of pairs is much smaller than their average separation is considered. The possibility of superfluidity of pairs is investigated, and the estimation of superfluid transition temperature is given. The conditions of competition between the superfluid transition and the pair crystallization with formation of a dipole crystal is discussed. The melting temperature of the dipole crystal is calculated in the assumption that the crystallization occurs according to the Kosterlitz-Thouless mechanism. The conditions under which the quantum effects prevent the crystallization down to zero temperature are determined. The problem of localization of pairs by impurities or structure irregularities is analyzed.