What to do and when to do it?

OK, life over the past few decades has been fun and fulfilling. As I look back, there are mixed feelings regarding things I should have done differently and things I am very glad that I completed/accomplished. How does one consider which things could have been changed without changing "where I am" today significantly. I like everything about my life - changing little things 30 years ago might have made major changes by now.

Well, nothing in the past can change and things are the way they are. Sooo, the questions is and will always will be "what to do and when to do it"? Should I go back to school and complete the 4 year degree or do I stick with what I have and use work experience to continue may career advances? Should I continue in the technology arena or should I move toward management or business (the last one would require more schooling). Hmmmm...