Without being at the event you are describing, it is difficult to predict an exact cure to the non dancing crowd. So, guessing the songs that may get the dancing going, is well just a guess, without being there to experience the solutions.
Having said that, choosing the best possible songs is obviously part of the equation to excite a crowd. Fortunately, I've had very little non-participating dancers over the many events I've done. Perhaps just a bit lucky or perhaps a little charm from the DJ helps too.
Music alone may not be all it takes. It could take a little mic work to "connect" with the audience. You can use dedications. When you dedicate a song to a couple they usually feel obligated to dance and others should/may follow.
Fill your crowd with compliments. When you make them feel like they look good on the dance floor they will be prone to remain out on the dance floor. Another thing you can do is use props. I will sometimes blow up balloons and put dollar bills in them. Of course your audience needs to be on the dance floor to be lucky enough to get a money filled balloon. Finding someone in your crowd that is their birthday. Finding a couple that is having their anniversary. Play a song for these couples. Finding a couple that have just recently got together, play a song for them. I have a list of about 30 songs I use to dedicate to a group or couples.
These "tricks" fall under the category of interaction, but they do help bring you and the crowd closer, and involves them with the music. And maybe, just maybe they will gravitate to the dancefloor.
As mentioned in other posts using crowd participation songs sometimes work, aka line dance music. I avoid these most of the time. But occasionally I'll even pull out cupid shuffle or cha cha slide.
There's some ideas to help create a more dancing
