  A candidate for the insulating phase of the 2D electron gas, seen in high
mobility 2D MOSFETS and heterojunctions, is a Wigner crystal pinned by the
incipient disorder. With this in view, we study the effect of collective
pinning on the physical properties of the crystal formed in zero external
magnetic field. We use an elastic theory to describe to long wavelength modes
of the crystal. The disorder is treated using the standard Gaussian variational
method. We calculate various physical properties of the system with particular
emphasis on their density dependence. We revisit the problem of compressibility
in this system and present results for the compressibility obtained via
effective capacitance measurements in experiments using bilayers. We present
results for the dynamical conductivity, surface acoustic wave anomalies and the
power radiated by the crystal through phonon emission at finite temperatures.
