Definitely, you want refereed papers in the top 5 conferences or journals in your field. That is, if you can. I mention conferences because in some fields conferences are refereed and are equally respected as top journals, but in most fields you want top-quality papers in top-quality journals. Period.
Academics (i.e. people who will look at you CV when you look for a job) know full well the huge gap between average papers and top-journal-quality (I would guess a subjective factor 2 to 5 at least). There are several reasons, besides the obvious ones, to aim high:
Tell your advisor your are aiming very high. See how (s)he reacts. (S)He will treat you accordingly (including telling you right off that he thinks you do not have what it takes if such is the case).
That will oblige you to chose interesting and relevant research questions. Papers about unimportant stuff never get published in top journals.
That will oblige you to make sure you advisor can coach you (is that where (s)he publishes?). If needed, you will switch advisor (or department, university) before wasting too much time.
On top of purely scientific results there are many things to learn from aiming high while you are still a student. That includes countless hours of rewriting, much better structure, language, dealing with referees who know their stuff, etc.
It does not make sense to go to school in a very competitive field and not try to do your absolute best.
Now is the time to learn from the best while you still call yourself a student and ask for help.
Top papers live longer, they still help you CV 10 years down the line (and accumulate citations meanwhile).
Average is boring, average is everywhere, average is... average.
Academia is a winner-takes-all game. Job openings are highly competitive. Candidate #1 gets the job, candidate #2 gets nothing more than candidate #10...
Of course you can go to a few conferences. Write a damn-good paper first, then try to present it to the best conference you can.
Btw, I published 4 papers out my PhD work in top-5 journals. The other two in good journals. I got a job.