What they mean by the sun will align with the milky way is this: When you look up and see the Milky way in the sky, there is a dark spot in the center of it. I believe they call it the great rift. The sun is said to align with this dark spot at the end of Mayan calendar.
AND I am not saying I think the world will end in 2012. I actually believe there are many reasons why it ends there.