A lot of users in my company are uploading a huge amount of files onto SharePoint2007. the problem is that the default setting is that all document are checked out. I would like to be able to change this default setting or check in multiple files at the same time. am new to the field and the job so if the solution requires running a script can you ...

Of course it's safe. Sharepoint can be deployed in various zones (default, intranet, extranet, custom) with different security policies in each zone. From IIS point of view each zone is a separate web application accessing the same Sharepoint content using separate security context.TSzIT-Dev Sharepoint components