From TMPGEnc site:
“TMPGEnc 4.0 XPress gives you the freedom to take almost any video file and encode it to your desired file format including DivX, AVI, QuickTime, MPEG 4-ISO, H.264, DVD-Video, DVD-VR, HDV camcorder, Blu-ray Disc and much more. This powerful software provides you with functions and features ranging from a simple cut-editor tool to multiple powerful video filtering and effects.”
“TMPGEnc DVD Author 3 with DivXÂ® Authoring is the perfect all-in-one DVD and DivXÂ® authoring solution for any video enthusiast, whether you’re a beginner or experienced videographer. It offers new features and some great improvements over its predecessors, such as HDV capture, DivXÂ® Ultra authoring, multiple subtitle streams, and the ability to add even more types of source files to your DVD and DivXÂ® projects. Of course, you can still cut-edit, create custom menus, and then burn your projects to DVD to show your friends and family!”
Simply put, TMPGEnc XPress encodes your movie to dvd compliant files and TMPGEnc DVD Author takes these dvd encoded video and audio files and compiles them to a format that your DVD Player can play.