I would say it is any one you will actually do consistently!
Jillian Michaels No More Trouble Zones. 6 months in and it never fails to make me MELT! Added bonus of very little jumping around and being embarrassed that my flatmates can hear me. (I do run for cardio also, so perhaps some of her others are better if you want more than just a strength workout.)
When I lost my weight there were no DVD players yet lol (back in 1987) but I heard Turbo Fire and Turbo Jam are GREAT for weight loss! There's a 30 day free trial for Turbo Fire going on right now too...inbox me for details!