Antiperspirants stop, or at least slow down, the operation of the sweat glands. And many of them contain aluminum. We went over some of the hazards of aluminum here.
On the other hand, a deodorant's job is to slow down the growth of bacteria. It allows the body to function normally and just controls odor.
There is some controversy as to whether or not antiperspirants increase your chance of breast cancer, but personally, I don't want to use anything that stops my body from functioning the way God intended.
I use a deodorant made by Tom's of Maine, but there are several on the market. Go out and find a scent that you like.