  We have systematically analyzed a sample of 13 new and archival ROSAT PSPC
observations of compact groups of galaxies: 12 Hickson Compact Groups plus the
NCG 2300 group. We find that approximately two-thirds of the groups have
extended X-ray emission and, in four of these, the emission is resolved into
diffuse emission from gas at a temperature of $k$T $\sim 1$ keV in the group
potential. All but one of the groups with extended emission have a spiral
fraction of less than 50\%. The baryon fraction of groups with diffuse emission
is 5--19\%, similar to the values in clusters of galaxies. However, with a
single exception (HCG 62), the gas-to-stellar-mass ratio in our groups has a
median value near 5\%, somewhat greater than the values for individual
early-type galaxies and two orders of magnitude lower than in clusters of
galaxies. The X-ray luminosities of individual group galaxies are comparable to
those of similar field galaxies, although the L$_X$-L$_B$ relation for
early-type galaxies may be flatter in compact groups than in the field.
