We report results from a combined analysis of solar neutrino data from all phases of the Sudbury Neutrino Observatory (SNO). By exploiting particle identification information obtained from the proportional counters installed during the third phase, this analysis improved background rejection in that phase of the experiment. The combined analysis of the SNO data resulted in a total flux of active neutrino flavors from B-8 decays in the Sun of (5.25 +/- 0.16(stat.)(-0.13)(+0.11)(syst.)) x 10(6) cm(-2)s(-1), while a two-flavor neutrino oscillation analysis yielded Delta m(21)(2) = (5.6(-1.4)(+1.9)) x 10(-5) eV(2) and tan(2) theta(12) = 0.427(-0.029)(+0.033). A three-flavor neutrino oscillation analysis combining the SNO result with results of all other solar neutrino experiments and reactor neutrino experiments yielded Delta m(21)(2) = (7.46(-0.19)(+0.20)) x 10(-5) eV(2), tan(2) theta(12) = 0.443(-0.025)(+0.030), and sin(2) theta(13) = (2.49(-0.32)(+0.20)) x 10(-2).