This is up to you. If you do, work out the feeding arrangements beforehand as many a good Ceilidh's been spoilt by a one and a half hour's break for the food to be served, eaten and cleared away, and a raffle held. A 20-minute break is ideal if there's no food - or 45 minutes, if you can manage it, if there is.
The easiest way to disrupt the enjoyment of a Ceilidh is to have a badly organised barbecue or hog roast. The food can be superb but human nature makes people join a food queue when they see one (there always is one with a barbecue), and the dancing stops for queueing, which is much less fun. If you have a barbecue, make sure all the food's ready to be instantly and quickly served before you declare it open.
The usual food at a Ceilidh these days is a Ploughman's but, whatever you choose, think about preparing or packaging it beforehand, so that you only need a couple of recruits to hand it out. Ploughman's, covered in cling film with pickle on a table in the middle, for instance, or even fish and chips brought in from the local shop, can be successful. The bigger your numbers, the bigger the problem if there’s a delay.
It is normal to feed the Band as well if everyone else is eating. Make sure that someone remembers and you could serve them early, so that they're ready to play before the dancers are ready to dance again.
If you need to book an outside bar, do that when you book the Band. It goes without saying that the earlier you get your publicity machine into action, the more people will come.