Going line dancing? Wear whatever is comfortable on your body, but pay attention to how you dress your feet!
You want to choose a shoe (or, if you are a purist, a boot) that moves well on the floor, and isn't too slippery. Dancers usually recommend a leather sole. Something like a boat shoe could be way too sticky on the floor and cause heel pain or tendon pain. Athletic shoes could have the same problem.
Avoid sandals or flip flops. With sandals, you run the risk of ruining the sandals with the back and forth motion of the dance. Meanwhile, flip flops offer no support at all and can actually trip you up on the floor if they don't move with the foot.
Try dance socks. They are fabric bands that slip over the front of sneakers and are widely used in Zumba classes.
If you are worried about blisters, be sure to wear socks without seams. You might try putting a little baby powder in the sock, too.