dj or no Dj?

Hi all,
My wedding is going to be small, 40-45 people and most of the guests will be ages 50-70 (family members). The venue I like doesn't allow bands but you can have a DJ. What I'm torn about is wether I go with a DJ knowing that for the odd song people will dance but most the time the dance floor will be empty.

Anyone else out there has this dilemma and what did you end up doing?
Thanks xox