I believe a single side DVD is 4700 Mbyte and should last about 2 hours. So that suggests half an hour should be around 1200 Mbyte. So 50Mbyte sounds like you may have compressed to a poor quality level. Just read 950mbyte for half an hour which sounds more like it. Should be fine quality. Don't know why Nero will not wiork. If it was bundled with your DVD burner it should work. I got Instand CD/DVD with my burner and that works fine.