xkcd

An annular eclipse happens when the moon is farther out, making it appear smaller than the sun. So when it covers it, you still see a ring of sun. Cool, but not spectacular. You need special glasses for sun viewing the entire time. It looks like so:

A total solar eclipse is when the moon is closer and appears as large or larger than the sun, completely blocking it. This creates a temporary night-like environment for a small section of the earth. It also makes it so that you can view the sun's outer atmosphere, which extends away from the sun in ghostly white outcroppings. This is always there, but the sun's surface is so bright it usually drowns it out. It appears about as bright as a full moon, viewable with the naked eye. The moon itself becomes absolutely, mesmerizingly black. Even very-science minded persons have described it as a religious experience