The increasing integration of inverter-based renewable energy sources (RESs) has significantly reduced the power grid inertia, leading to challenges in maintaining frequency stability. Virtual synchronous generators (VSGs), which emulate the behavior of synchronous generators (SGs), can help address this issue by providing synthetic inertia and improving system stability during disturbances. The paralleled operation of VSGs and SGs is particularly important in islanded microgrids, where small SGs are commonly used for power generation. This paper presents a comprehensive dynamic model of a paralleled VSG-SG system and proposes a model predictive control (MPC) strategy for VSG to enhance disturbance rejection and improve dynamic performance. Additionally, an adaptive delay compensator (ADC) is introduced to manage communication delays between the control center and system. Simulation results in MATLAB/Simulink demonstrate the effectiveness of the MPC-based VSG control method in improving frequency control in various disturbance scenarios.