Ten Thousand Steps A Day

This is a picture of my pedometer.  A pedometer is an instrument worn by a walker or runner for recording the number of steps taken, thereby showing approximately the distance traveled.  I bought it at Walmart for $5.00 and I wear it everywhere I go.
My goal is to walk 10,000 steps a day.  This equals approximately five miles.  I try to walk at least a mile at a time without stopping to rest.  I would eventually like to be able to walk the full five miles without stopping.
I have never been the athletic type.  I don't expecially enjoy exercise but I know that it is something that I MUST do.  I am reading Younger Next Year: Live Strong, Fit, and Sexy - Until You're 80 and Beyond by Chris Crowley and Henry Lodge.  They are very emphatic in stating that a person who is over the age of 50 needs to commit to at least an hour of exercise a day...six days a week. They state that exercise should be your full-time job after you retire. 
I am now 57 years old.  I just watched my father die from heart disease at the age of 84.  I want to do everything in my power to avoid this fate.  Exercise is my priority.  I have two metal plates in my right leg so I can't run, jump, skip, stomp or do high impact exercise.  I have discovered plenty of things that I can do and I hope to slowly increase the amount of exercise that I do each day.
Do you believe that exercise can slow the aging process?  What is your daily exercise routine?  I hope you will share some of your exercise experiences by posting a comment on this blog.