I'd go straight for theCardio hits (Step Fit, Powermax, Step Works), Cardio & Weights from the I series and Imax 2. I think the Classics will be too easy and slightly boring for choreography quite quickly. It won't keep you challenged for long.
Clare
Edited to add: Or just go straight for the CTX series and enjoy a variety of intense cardio workouts with a variety of styles, plus a tough upper body split workout, a fab lower body workout and a variety of ab/core workouts featuring planks and traditional abs. In fact, the CTX series is the best value and you will grow with it for a long time in all areas of fitness.