I think one of the major issues that (we) Baptist have is that we have tried to overcompensate for everything out of opposition to certain behavior in other denominations.
When the Catholics started becoming a force, proclaiming that it was good works that get you to Heaven, many Baptist stood against this by saying, "Hey, the Catholics are wrong, do whatever you want, you will still go to Heaven." While, this is true, it has given people the idea that God does not care what we do with our lives, so long as we are saved.
When the Charismatics came along with the touchy-feely emotion based beliefs, the Baptist stood against it by saying "Emotions are the Devil! Disregard every emotion that you have because it is evil and carnal." I have even heard Baptists say that certain music was bad because it appealed to your emotions. The problem is that God created us with emotions for a reason. He wants us to get mad and happy and feel good when we do right.
The problem is that Fundamentalist preachers get up and preach that a good Baptist man has short hair, doesn't drink, doesn't smoke, doesn't gamble and doesn't dance. The problem is that we are defining ourselves by what we DON'T do, instead of what we do.
If we Baptists are really going to be able to say that we are the ones following the Bible, we need to start defining ourselves by what the Bible says we are supposed to do.
Well, I got a little off track. Back to the OP. Many Fundamental Baptists don't dance because they consider it, as I have heard it said many times "A vertical representation of a horizontal action". There is a lot of sexual connotation to much of the dancing that goes on today. Personally, I do not think that there is anything wrong with certain kinds of dancing, but when the gyrations and moves start to emphasize a persons body, they are not glorifying the Lord, they are showing off their bodies.