What could be causing the window on my 1998 Plymouth Grand Voyager not to engage and lower/raise the windows?

Driver side window sometimes does not go down; the motor whines when the electric switch is engaged. With the aid of a screw drive pressing on the nub beneath the switch the window might go down. The penger side window is also stuck (up or down). Thoughts? New window motor needed? Remove panel and see if electrical is at issue? Thanks for your inputs. Robert C