How to edit Sales Order form?

Dear Friends,

Sorry if I am asking a lame/ obvious questions.

I want to change a few things on the Sales Order form. The default sales order form which is automatically generated after by "Sales Order Entery" looks good however I would like to add a a few static lines to the final printable Sales Order From. 

Also is there a setting page to edit/eliminate the title of the fields or choose which fields to be included/shown on the Sales order Form?

Your help is much appreciated.