Mortimer Adler has written some philosophy books that are accessible, like How to Think About the Great Ideas: From the Great Books of Western Civilization.
You're obviously well educated on the subject. I agree with what you're saying. That's why my recommendation above was to do Bootstrapping Squats (at first), bench, deadlifts and chins -- just the basics. You especially want to strengthen the Posterior Chain (hamstrings, glutes, lower back) and Bootstrapper Squats are a simple way to get started.
There's a great book called Starting Strength that gives a basic starting program.
Some of the exercises in the links you give are okay. Front squats are an especially advanced exercise--a lot harder than they look. And bench presses won't give you rounded shoulders.
I'd recommend Bootstrapper Squats (google it) or regular barbell squats, bench press, shoulder press, deadlifts and chins.
Riding a bike is an excellent warmup for your knees prior to doing any kind of leg work.
And bench presses won't give you rounded shoulders.
Healthy shoulders are a result of a balance between the static tension of the upper back muscles and the chest muscles. If you already have rounded shoulders, it means that the chest muscles are too strong and too contracted, while the upper back muscles too weak. That's why a personal trainer or a doctor will prescribe regular _stretching_ of the chest muscles as part of a treatment for this condition. If you're healthy, then bench pressing won't give you rounded shoulders, provided that you balance the training appropriately with upper back exercises. But the point is that people with sedentary lifestyles tend to have their chest muscles already chronically contracted from the posture they keep for most of the day, so they should first work on stretching the chest muscles and strengthening the upper back. When their posture is balanced again, they can workout normally, balancing bench pressing with rowing exercises.
Front squats are a little tricky (balance and flexibility in both hips and arms/wrists matter), but as with any movement, starting light (prop or unloaded bar) isn't going to hurt anyone (well, anyone who's not already hurt or missing body parts).
I just looked up Boostrap Squats. Not sold, but Dan John is a solid guy.
Cycling's OK for lower body, but I'd pick erging (indoor rowing) for a better whole-body warm-up.
Huge fan of the basic Rippetoe movements: squats, deads, bench, press (a/k/a shoulder press), chins, rows, and power cleans.
http://www.amazon.com/How-Think-About-Great-Ideas/dp/0812694...