Starting with a 1/2 marathon is definitely a good idea. Then you can see how much you like it, how easy it is to train, etc. If you're a regular runner now, you should have no problem progressing up to the 1/2 distance.
"You may have a fresh start any moment you choose, for this thing that we call "failure" is not the falling down but the staying down." Mary Pickford
"No matter how slow you go, you are still lapping everybody on the couch."