I second the emotions about the CTX series and the Timesaver. I think each of these will be a good pathway into more of what Cathe has to offer.
The CTX ("Cross Train Express") series is a 2-disc set that contains 4 complete workouts on one DVD (each of which includes a cardio component, isolated-muscle strength training component, and at least 2 ab workouts), and 2 complete workouts on the other DVD (one of which is another cardio+strength+ab routine and the 6th of which is a leg-strengthening blaster called "Leaner Legs" that also has a great traditional ab routine). The other DVD also has a composite of all of the upper body strength segments AND all of the ab segments in separate premixes. CTX is great because it offers several cardio modes AND introduces you to interval blasts in Step Intervals and 10-10-10.
The Timesaver DVD was created from existing footage from the Body Blast Series and adds bonus footage. It too offers cardio + strengthening components into 5 separate workouts. You'll get used to more complex choreography, and higher intensity, in Timesaver, as you will as well with CTX.
A-Jock