no, a presentation is not a publication, even if the abstract is put into the symposium's program, I mean I guess technically it can be, but who are you trying to fool, these are PhD's and MD's who are looking at your application.
How far is the progress of the two papers you speak of? If they've been submitted then go ahead and list them as publications, just be sure to say that at the end of the citation (say its submitted and give a date or if its under review give a date when the editor sent you an update etc)
technically even something that's been submitted isn't really a publication, as its not 100% that its going to get published but adcoms will be more sympathetic (cus its alot of work to prepare a manuscript) and will prob review your app more closely. I believe Lizzy says not to list them but really its up to you, but again people who have been doing research their entire life will know the truth.
BTW are you primary author on these papers or abstract? if not speak with a softer tone, else whoever's first author on those papers would feel pretty offended