To the OP...a peace offering.
I suspect that you may already know the 10 most common openings. But, here they are.
IMO, it isn't necessary to remember the names but just the concepts. Too, there are many subset variations. Probably, since this would take effort to learn...don't fret about them.
Anyway: http://chess.about.com/od/openings/tp/TopOpenings.htm
P.S.: And, no...I'm not being condescending. This is simply a peace offering.
Thanks, peace offering accepted 
The thing I realized, playing in class sections in tournaments, is: my opponents were not REALLY booked up, either. I was stressing out about my openings, and they were actually good enough for where I was, even in main line stuff like Sicilians. I was losing games from having a bad opening very, very rarely. My losses were from poor middlegame or ending play, planless drifting into a bad game, or from blunders. So I quit looking at openings for a year, and worked on tactics,basic endings, and looking at annotated games. It did me a world of good.
If you want to break 2000, and stay there, though, strong players tell me that you just have to put in some serious work on building a good repetoire. Every game at that level is with a good player, everyone plays tight, everyone has good openings. Everyone knows how to jump on bad opening moves. (My current goal is to get and stay over 1800 OTB- I'm just a club patzer, so take chess advice from me at your own risk).
I have very similar experience - from about 30 OTB games against 1500-1900 players I remember may be 3 games where things went wrong in the opening.
I will go on with my plan of low investment in opening preparation . If I break 1800 one day I might reconsider it again.
The thing I realized, playing in class sections in tournaments, is: my opponents were not REALLY booked up, either. I was stressing out about my openings, and they were actually good enough for where I was, even in main line stuff like Sicilians. I was losing games from having a bad opening very, very rarely. My losses were from poor middlegame or ending play, planless drifting into a bad game, or from blunders. So I quit looking at openings for a year, and worked on tactics,basic endings, and looking at annotated games. It did me a world of good.
If you want to break 2000, and stay there, though, strong players tell me that you just have to put in some serious work on building a good repetoire. Every game at that level is with a good player, everyone plays tight, everyone has good openings. Everyone knows how to jump on bad opening moves. (My current goal is to get and stay over 1800 OTB- I'm just a club patzer, so take chess advice from me at your own risk).