Polarization digital holographic microscopy (PDHM) enables noninvasive, quantitative mapping of birefringence via full-field Jones matrix analysis. Conventional implementations rely on multiple sequential acquisitions and are vulnerable to phase drift, whereas single-shot variants are optically complex and alignment sensitive. We introduce a simple dual-shot PDHM that reconstructs the full-field Jones matrix from two holograms acquired with orthogonal incident polarizations. A motorized half-wave plate sets the input states, and a polarization-sensitive CMOS camera records off-axis holograms that embed four analyzer channels per exposure. To suppress inter-shot phase drift, we propose a phase bias equalization that leverages isotropic reference regions to align complex phases across Jones elements. Experiments on biaxially oriented polypropylene (BOPP) films yield retardance and fast axis maps in agreement. Imaging of mouse brain sections and human cornea further demonstrates robust visualization of anisotropic microstructures. The method balances speed, hardware simplicity, and quantitative performance, offering an accessible route to polarization-sensitive biomedical imaging and full-field Jones matrix microscopy.