  Raman scattering spectra of new Fe-based S=2 spin ladder compound
BaFe$_2$Se$_2$O are measured in a temperature range between 15 K and 623 K. All
six A$_{1g}$ and two B$_{1g}$ Raman active modes of BaFe$_2$Se$_2$O, predicted
by the factor-group analysis, have been experimentally observed at energies
that are in a rather good agreement with the lattice dynamics calculation. The
antiferromagnetic long-range spin ordering in BaFe$_2$Se$_2$O below $T_N$=240 K
leaves a fingerprint both in the A$_{1g}$ and B$_{1g}$ phonon mode linewidth
and energy. In the energy range between 400 and 650 cm$^{-1}$ we have observed
magnetic excitation related structure in the form of magnon continuum, with the
peaks corresponding to the singularities in the one dimensional density of
magnon states. The onset value of magnetic continuum (2$\Delta_{S}$) is found
at about 437 cm$^{-1}$ at 15 K. The magnetic continuum disappears at about 623
K, which lead us to conclude that the short-range magnetic ordering in
BaFe$_2$Se$_2$O exists apparently up to 2.6$T_N$.
