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We compile the currently most complete sample of almost 5000 Galactic RR Lyrae variables with available radial-velocity and spectroscopic [Fe/H] measurements adopted from dedicated studies (about 440 stars), large-scale spectroscopic surveys (SDSS, RAVE, LAMOST, a total of over 4200 stars), and based on the results of our program aimed at acquiring spectra of relatively bright RR Lyrae variables carried out at South African Large Telescope yielded radial velocities and metallicities (~200 hitherto spectroscopically unexplored RR Lyraes). We complement the radial-velocity data for these stars with accurate proper motions from the upcoming Tycho-Gaia catalog and compute proper motions for fainter stars based on the UCAC4, URAT1, 2MASS, and WISE, and DSS Schmidt plate positions reduced to the frame defined by UCAC4 catalog. We further determine the mutually consistent preliminary distances to our RR Lyraes based on our recent calibrations (Dambis et al. 2013, 2014) applied to WISE infrared data, published photoelectric and CCD V-band data, reduced Catalina Sky Survey data, and our own photoelectric (more than 1200 multicolor measurements) and CCD (more than 40000 frames) photometry. We use the 3D velocity data obtained to perform a statistical-parallax analysis for a subsample of ~1000 RR Lyraes brighter than V=16m to refine the parameters of optical and IR period-metallicity-luminosity relations and adjust our preliminary distances. We use the kinematic data for the entire sample to explore the dependence of the halo and thick-disk RR Lyrae velocity ellipsoids on Galactocentric distance from the inner bulge out to R~50 kpc, probe the mass distribution in the Galactic halo, and estimate the distance to the Galactic center.