I've always been super unflexible (my trainer at one time said stretching me was like working with an elderly rehab patient), have put on +25% of my body weight since I got married 10 years ago, my cardio is shot to the point where 30 mins of light tennis and I'm huffing, I've got a bad disc in my neck and likely a bulging disc in my back.
How in the world would I get started? And which of the above issues would it help with? I've been thinking about it, but have no idea what's feasible or where to begin.