Setting up Backup and Samba Permmissions

Hello We heve built a linux gentoo server, we need a little work done to our server in order to back up our information. We have recently added a dvd burner to our system and want write to it, our files, to back them up onto dvd. We also have samba file server installed on the server. The project requirements: 1. Make gentoo "see" the new dvd writer [login to view URL] necessary (free) software to write files (tar) to dvd sequentially on a daily basis or suggest and alternative way 3. Modify groups and users so that all the people in the group can create and modify all files when created using samba.