We present the density-functional approach to study the isotropic-nematic transitions and calculate the values of freezing parameters of the Gay-Berne liquid crystal model, concentrating on the effects of varying the molecular elongation, x 0 . For this, we have solved the Percus-Yevick integral equation theory to calculate the pair-correlation functions of a fluid the molecules of which interact via a Gay-Berne pair potential. These results have been used in the density-functional theory as an input to locate the isotropic-nematic transition and calculate freezing parameters for a range of length-to-width parameters 3.0=<x 0 =<4.0 at reduced temperatures 0.95 and 1.25. We observed that as x 0 is increased, the isotropic-nematic transition is seen to move to lower density at a given temperature. We find that the density-functional theory is good to study the freezing transitions in such fluids. We have also compared our results with computer simulation results wherever they are available.