2ManDVD is a full featured dvd authoring application with a nice looking
qt interface written by Stéphane Gibault.  It's the successor of ManDVD
written for qt4 and webkit.

for a faster gui the author suggests try launching it from command line 
with option "-graphicssystem raster" or "-graphicssystem opengl"

This requires webkit, ffmpeg, transcode, dvdauthor, mjpegtools, and 
ffmpegthumbnailer.