I like gardening as I find it to be very relaxing, as do many other people I think.
What is relaxing about gardening? 
Well just being able to care for your fruits, herbs, and vegetables and watching them grow feels very peaceful to me, like their your children.
Do you save money growing your own garden? 
I save a bit because I don't have to buy as many root and leaf vegetables from the store, but you spend a bit on the fertilizer and soil too.
What is the easiest plant to start gardening with? 
I think ornamental plants are pretty easy, but some people say stuff like carrots are very easy to start out with as well.
Ornamental plants are flowers? I am so clueless when it comes to gardening. 
Basically, ornamental plants are plants grown for decorative purposes due to their flowers as you mentioned, and other aesthetic features.
I love buying flowers at the market. I may give it a try, what flower would you recommend I start with?