I am trying to install and run Spree on my local machine by following the steps mentioned in Getting started with Spree
However, when I start the server I get the follow
Could not find table 'pages' means rails is not being able to find that table in the database.
In those instructions, review the section 'configuring the database' and then '4.6 Populating the Database'.
It sounds like you want to give spree a go, but don't have experience with Rails. The spot where you are stuck is not something specific to spree, its a step required in setting up all rails projects referred to as database migration.
For what you need to know about migrations the official Rails Guides are great. http://guides.rubyonrails.org/migrations.html
For a comprehensive intro to Rails which may also answer a few of your other questions, check out http://railstutorial.org/ruby-on-rails-tutorial-book
If you just want to try stuff.. the spree tute is on track Do these steps again.. (If it generates an error, to a rake db:drop first to get rid of what you have already done)