An analysis is carried out to study the flow and heat transfer of electrically conducting immiscible viscous fluids in a parallel vertical channel. Both fluids are incompressible and the flow is assumed to be steady, one dimensional and fully developed. Combined free and forced convection inside the channel is considered. Through proper choice of dimensionless variables, the governing equations are developed and three types of thermal boundary conditions are prescribed. These thermal boundary conditions are isothermal-isothermal, isoflux-isothermal and isothermal-isoflux for the left-right walls of the channel respectively. The basic equations are solved analytically using the regular perturbation method and numerically using Runge-Kutta-Gill method. Solutions for the velocity and temperature for the various special cases are reported. A selected set of graphical results illustrating the effects of various parameters involved in the problem on the velocity and temperature profiles as well as flow reversal situation and Nusselt number is presented and discussed.