I have all of Cathe's workouts except the Basic Step/Body Fusion which I didnt purchase b/c I thought they would be too basic so I cant comment on them. I'd definitely purchase a full length club step as has been previously mentioned. Also I wanted to add not let a particular cardio/weights combo workout detour you b/c most of Cathe's dvds have premixes on them so you can just do the cardio or just do the weights. That said, here's what I consider to be a good starter list considering the workouts as is ie. no premix....
1. Kick Punch & Crunch/Legs & Glutes dvd---great nonstep workout plus a great leg workout, the abs on KPC are great too! KPC is a great cardio workout to do while trying to learn step.
2. Pyramid Upper and Lower Body dvd---a must have strength workout
3. IMax2/Cardio & Weights dvd---IMAX2 isnt too tough to learn, and it's alot of fun, C&W is another easier to pick up step routine (it has a cardio only premix)
4. The Pure Strength series dvd is another no-nonsense strength training workout that gives you the opportunity for a split routine instead of a total body workout
5. As far as other basic step workouts, Cathe has a ton as you've noticed. Her older ones are a little easier to learn, but the dated workout-wear bothers some people. Her older ones that arent too tough to learn include, Mega Step Blast, Step Heat, Step Max, Power Max. Her new Step Blast/Step Jump & Pump dvd is THE most fun and has the best music of any step workout I've ever done, and it's not too tough to learn once you have some basic moves down. Again, this one has tons of cardio only premixes that incorporate both step routines.
6. I wanted to add that Push Pull/Supersets is another great investment. The workouts as is are some of Cathe's easiest weight routines, but the variety of premixes toughen them up! However, this dvd was great for me recently b/c I'm getting over an illness and needed something on the lighter side to get me back into the groove and this dvd fit the bill.
Merry Christmas!