I have been programming in Python for a few years. I have heard a lot about Lisp on HN. What is a good way for me to start learning Lisp?

Which dialect? Common Lisp? Which compiler should I use? SBCL? Do I have to learn Emacs?

My motivation to learn is to satisfy my curiosity and also write some useful programs for myself in future.

Can Common Lisp be a good substitute for Python for personal scripting needs?