In this work, we report on a detailed study of the diffusional and vibrational dynamics of liquid ethylene glycol (EG: HO-CH2CH2-OH) in the bulk state and confined in a matrix of sol-gel porous glass with 26 A interconnected cylindrical pores. The investigation is performed, by incoherent quasielastic and inelastic neutron scattering (IQENS and IINS), as a function of temperature. IQENS data have been definitively interpreted in terms of the alpha-relaxation dynamics predicted by mode coupling theory for supercooled liquids. We verified that a description by means of an Havriliak-Negami profile is consistent with the measured spectral line shape. Furthermore, IINS spectra show a clear different evolution versus T of the vibrational density of states, Z(omega), passing from the bulk samples to the confined ones, revealing, in particular, a thermal stabilization of the disordered longitudinal acoustic mode induced by interaction of EG molecules with the active silanol (Si-OH) groups of the surface. (C) 2003 American Institute of Physics.