How should a 40 year old live?

Is 40 too old for watching kids' shows?  What should I do?  How should I live my life?  I believe now that age is just a number, in most cases.  I have learned to embrace being 40 at the age of 40.  So far that has been all I have done.  I didn't worry as much about my age as I once did, and that is a good thing.  I don't understand how then I obsessed so much about an uncertain future.  The past was full of troubles in itself.