The tutorial link is a resource for these often asked basic questions
1. get rid of the Congratulations! You have successfully installed your Zen Cart™ E-Commerce Solution. on the main page.
I searched for Congratulations

https://www.zen-cart.com/tutorials/i...hp?article=129
2. Where can I change the title of the store front page.
it says Zen Cart!. The Art of E-commerce.
I searched for Zen Cart

https://www.zen-cart.com/tutorials/index.php?article=17

And if there is one addon you'd include in a new cart, what would it be? A must have?
Depends upon what you site is