How about strength training? The gym styles have premixes and so do PU and PL. I think it's good at almost any level because you can drop your weight down, even during a set if you need to and I think the premixes are only about half an hour. Also you can stop earlier by leaving off reps if you need to. I didn't think P90x would be that bad since you do as much as you can but due to the amount of pull-up versions and pushup versions it can be quite intimidating for a newer exerciser, I’ve scared people off with these. As far as cardio, Cathe is pretty tough and if your friend is not very fit, it maybe something she needs to work up to. The cathe beginner series that was at target a while back was very doable, I bought it for my mother who was not active and had not worked out in years.
Good luck and I hope that helps.
~Angel