Ohhh.....I wouldn't worry about starting "at the beginning". Everyone starts somewhere, right? I actually have just allowed myself to start doing step again, but only 1x a week while I see what my knees can currently handle, and am theoretically only doing Basic Step, Low Max and Cardio and Weights. But I had to try Intensity.....cause......
For some reason, Cardio and Weights will always be one of my favorites. It's just fun to me, and the "Buttercup" song at the end really makes me happy. Although it's not a happy song, lyric-wise, go figure.
Anyway, I know I'm new, but I have been lurking for years, and I just wanted to give you encouragement, because I used to feel the same way. Somehow along the way, though, I've changed, and when I run into something fitness-wise that is challenging for me, I can (sometimes) say "oh good, I have lots to work up to, it will be fun." Not always though.