The NETBIOS name can be edited in the Network Preference pane: Select the network connection currently in use on the left, click the "Advanced..." button then the "WINS" tab. Edit the name there.
Specifically it is there so that you can share files with Windows-based PCs via SMB. You can turn that option off under the Sharing Preference pane, then click on File Sharing and the Options button and uncheck "Share files and folders via SMB."
I have the same OS and see no "Network Neighborhood." That is Windows Nomenclature and might be that you are seeing a Windows PC or PCs on your local network. Some people have file sharing turned on and don't realize it.
Remote disc is a way of sharing an optical drive from a Mac that has one to a Mac that doesn't. You can choose what you seen the Finder sidebar by going to the Finder (I just usually open a new Finder window) and tap COMMAND , (or go the the Finder menu and select preferences). Then click on the sidebar tab and check or un-check the items you do or do not want to see.