Microcontroller

I want to ask how to learn micocontroller well
i.e which books should I read?, which programing languages should I learn?
which microcontroller should I use?

an easy one that i started out with was the basic stamp 2. it's pretty expensive compared to pics but there is also allot of really great documentation on the parallax web site. i'm just starting with pics but i'm sure allot of the more experienced members can help with that