Welcome to ImgBurn Forum.
Just select the files/folders and go as you normally would. DVD Video requires special settings in the Options field.
For data files, in build mode, you might want to tick Preserve Full Pathname and the Recurse Options. If you only wanna backup files that have changed since a major backup, tick Include Archive Files Only (those with the Archive bit set). Keep the filesystem at ISO9660 and UDF
Regards