A healthy mind is one thing, but to get the most out of life it really needs to come in a healthy body. Physical training is also incredibly good fun. There is a purity about weight training and time training that you get in few other sporting contexts - a purity that comes from the fact that it is so simple to measure progress.
I have been through a whole gamut of training programmes in my time, some designed solely to build muscle, some designed for strength, some for fitness. Just like a good recipe, if what you want is a body that will enable you to get the most out of life for the longest possible time, then the key is to balance these components. I have, however, included my old strength and bodybuilding programmes here for people who don't really want a balance.
Warning: Always undertake free weight training only with a partner strong enough to spot you properly, only if you have had training in techniques, ideally under supervision, and always use perfect form. Never cheat to lift a little bit extra weight. And if you feel any kind of pain that you are unsure about (hey, getting strong's all about putting yourself through pain, but NOT the kind of pain that injures you) stop and seek immediate first aid - the quicker you get ice or heat on, the less damage you'll do. Finally, always wear adequate support - that means a belt that's up to the job, knee supports, elbow supports, and an all-in-one if you're doing serious powerlifting.
That's the nannying over with (just covering my back!)