The first four Ramones albums were unassailable genre-defining masterworks, but the 12 that followed were pretty damn spotty. Which is why Hey Go Let's Go! The Ramones Anthology, a chronological two-CD retrospective, is so frustrating the careerist competency of later songs like ''Something to Believe In'' feels hollow and false compared with the punky perfection of, say, ''53rd & 3rd.'' Still, the great early stuff on the first CD hits so straight, deep, and true, it'd be churlish to judge this well-intentioned collection too harshly. Since it all began with ''Blitzkrieg Bop,'' let's give it a B.