definitely focus on the boards. and being involved is probably better than having a research project. also, while a lot of people focus on ortho research, it doesnt really matter what type of research you do. i have all basic science research, no clinical.... if it is ever discussed (only on 2 interviews so far) it seems to go over well. in fact, theres a sort of novelty that goes along with non-ortho research. plus i can say pretty much whatever b/c most lack any knowledge on the subject... not that ive heard of it happening, but i suppose you could really get grilled on your ortho research on interviews. that said, those days in the lab are hours ill never get back and knowledge ill probably never use.
focus on step i and do stuff to make you look interesting on interviews. step i gets you interviews... youll need something to set you apart on those days. unfortunately, everyone there has research, so try to bring something else to the table.