We have observed resonant Raman scattering (RRS) and photoluminescence (PL) enhancement due to resonant absorption of the exciting light in low temperature experiments on a 50 Angstrom Zn0.74Cd0.26Se quantum well (QW) confined by ZnSe barriers. The spectra presents a sharp and very intense Stokes longitudinal optical (LO) phonon at 31.1 meV and also a weak 2LO mode. We show that the RRS is due to a double resonance: the first is produced by the matching of the exciting laser line (488 nm, 2.5407 eV) with the 1hh --> 1e absorption transition of the QW; the second is due to the coincidence of the exciton binding energy (determined as 32.6+/-2 meV) and the LO phonon energy. A selective increase of the intensity of one of the PL excitonic peaks takes place when islands of 50 Angstrom thickness of the QW are resonantly excited with the 488 nm laser line; the relative intensity of this peak increases one order: of magnitude in relation to other excitonic peak situated around 9 meV below.