I would modify LetsGoDance's recommendations to be a little heavier in Foxtrot (of course the distribution varies with the audience). And I also recommend this document:

http://www.mrk-inc.com/users/fjacoby/ballrm0.pdf

It is a little book written by a bandleader who is also a dancer. He talks about the correct tempo for dancing, and why it matters. Music that is too fast or too slow for a given dance is simply harder (or impossible) to dance to than music in the correct tempo. This author's discussion of this topic is clear and to the point. Since the original poster says his band is "inexperienced at playing for dancers," this book could be helpful.