[Koha] Customizing the look of Koha (questions)

OK... Now I have it running... I have two questions... How do I remove the Branch in the default setup? There was a branch already installed and can't remove it... it says it is being used... How do I create a whole new database/set of files for Koha to use so I can start from scratch... Also... how do I modify the look of KOHA... Specifically the colors of the OPAC page and putting our school logo on the page... I also want to simplify the OPAC slightly since we are an elementary school...(maybe remove a few choices here and there) THANKS Philip Lathroum Technology Coordinator Cardinal Shehan School 410-433-2775 x107