If diet is 80%, why would you bother with exercise? Diet is 80% of how you look but how your body moves is another story. The old cliche "move it or lose it" applies to you. Ever see a man who was fairly active retire and rapidly turn into an immobile old man? That's what a sedentary lifestyle will eventually do to you.
My philosophy on exercise is a combination of CrossFit's and a few other sources. Your exercise should be hard and intense. Like with diet, I look to what nature has given us. If you're a hunter, you would conserve energy until you needed in, in which case you would expend large amounts of effort and then get plenty of rest. Picture a wild lion. They lay around most of the day, but when they hunt down prey they are fast and vicious. They don't spend time in the fat burning zone or check their heart beats.
I know, jogging is a great way to lose weight. I've done it myself and was fairly happy with the results. Then I noticed the difference in the bodies of distance joggers verses the bodies of sprinters. The sprinters were leaner, more muscular and looked healthier overall. Also, jogging bores me.
When you lift, lift heavy. Force your body to become stronger. If you're doing 12 reps of some exercise and running your mouth about some TV show you saw last night, you're wasting your time. Heavy for you is different than it is for the next person. Don't worry if some guy can bench 400 pounds and you struggle with 95. Just worry about improving yourself.
If you can't get to a gym, don't worry. I'm not a big fan of commercial gyms anyway. The majority of the machines are useless. 95% of the people there just like the social aspect. Most of the trainers don't know how to perform the exercises right. You don't need it. There are great body weight exercises you can do. Running is free.
If you want something, don't spend a ton of money on some huge piece of equipment that you have to sacrifice a room for. I'm sure the Bowflex is great, but you don't need it. The Gazel sucks. The ROM is an expensive hunk of garbage. Get your hands on a kettlebell.
What is a kettlebel?
Think of it as a cannonball with a handle. The kettlebell has been around for a long time and has long been used in Russia and kettlebell lifting is even a national sport there. It is a great home gym in that you can use it to build strength, improve cardio, even work on coordination; there's a reason they are popular with MMA fighters. When you're done, just put in in the closet.
With all of that said, here are a few sites I recommend you visit:
1.
CrossFit - Again, where it all started over for me. CrossFit is about being proficient in as much as possible. The work outs are comprised of power lifting movements, olympic lifting movements, gymnastic skills, and much much more. The focus is on intensity. How quickly can you do 150 burpees? How many pull-ups, push-ups, and squats can you do in 20 minutes? What is your 1 rep max in the overhead press? CrossFit covers it all. The focus is on performance. Don't think you can hang? Every workout is scalable to your fitness level and what kind of equipment you have. Remember how good the guys in 300 looked? This is where many of their training ideas came from.
2.
Performance Menu - PM is similar to CrossFit with the focus being mainly on strength. You still get a good conditioning workout, but typically the metabolic workouts are short in order to keep your cardio in good shape while still focusing your attention on being as strong as possible.
3.
Dragon Door - THE place to go for all of your kettlebell needs. Pavel Tsatsouline is a Russian strength and conditioning expert who lives exercise and his specialty is the kettlebell. I highly recommend any and all of his books.
Naked Warrior is about body weight only exercises.
Enter the Kettlebell is a great introduction to the Kettlebell.
Power to the People is your guide to gaining strength with 2 sets of deadlifts and presses a day. The man knows what he's talking about.
Dragon Door kettlebells are also the best I've used. They are a bit more expensive than others, but they have the best handles and are very well balanced. You can also find a good deal on eBay that can save you up to $100 at times. If your a guy a 16 Kg or 20 Kg bell and the Enter the Kettlebell DVD with is a great introduction. If your a woman, 8 Kg or 12 Kg bell with the The Kettlebell Goddess Workout> DVD is a good start.
I'm only listed 3 websites because they are the main 3 I go to. All three cover weight loss, cardio fitness and strength training. Just about anything you want to know can be found here. The forums are excellent sources of information and they are very welcoming to new people.
As always, talk to your doctor, blah blah blah. Work hard and work smart. You'll be glad you did when you're 60 and can still move well.