what "thrash"?
Generally stuff that people play in blitz and would never try in an OTB game. 1. b3 : not trash but 1. b4 trash [IMO]. It's arguable of course but I think Schliemann: not trash, delayed Schliemann : borderline trash. Smith-Morra: borderline but BlackmarDiemer: trash. All just my opinion,-Bill
oh no you didnt!
OK -- school me then!
My repertoire is always being refined and adjusted, but I tend to play just a few openings. Currently as white I play the Kings Indian Attack with 1. e4, and as black I currently play the Kings Indian Defense and the Pirc, which are almost the same thing. It cuts down on the number of openings you have to study, and they all have very similar middlegame strategies and tactics. Somebody earlier said you should expose yourself to a wide variety of openings, which I agree with except, not all at once. I used to play the Benoni, Sicilian, and Vienna Game, and before that I played the London and Sicilian. When you're ready you explore something different.
To combine a few pieces of advice already given, I think it goes like this...
When you're new, focus on a few solid openings with clear ideas. Like queen's gambit declined.
When you're past the beginner stage, it's good to experiment with a lot of different types of middlegames (i.e. openings).
But after acquiring a well rounded knowledge, it's best to focus on a few openings again, and this time learn them deeply.