This study investigates the performance of diversity combining techniques to enhance wireless communication reliability over fading channels. Specifically, it compares conventional Selection Combining (SC) and Maximal Ratio Combining (MRC) for two-dimensional modulation schemes, such as M-ary Phase Shift Keying (MPSK) and M-ary Quadrature Amplitude Modulation (MQAM). The analysis focuses on Symbol Error Rate (SER) and Bit Error Rate (BER) as key performance metrics, considering both paired and non-paired real and imaginary signal components. Results demonstrate that Enhanced MRC offers a significant Signal-to-Noise Ratio (SNR) advantage over Enhanced SC, with performance gains increasing with higher diversity orders. Theoretical derivations and simulations validate these findings, highlighting MRC's superiority in mitigating fading effects.