Hello again MrRob, glad to see you've come back!

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Sounds like you have a reason to be motivated, what with a baby on the way...
MrRob, please start by understanding that there is no "perfect plan" that fits all people. There is no "perfect diet" that fits all people, etc. etc....
The only "constant" that applies to everybody (and I mean everybody!) is consistency in one's approach to fitness. Don't give up too easily because results take time- often A LOT of time.
That being said, a basic full-body workout will get you started for the first month or two. Get into the motions, don't worry about adding lots of weight yet- just work within your comfort zone and get your form back.
Workout 1
Bench press
DB row (your body will be supported on the bench, so lower back should be okay)
DB shoulder press
Leg extension or squat (do whichever does not hurt your joints)
Leg curl
Calf extension (1 leg at a time, holding a DB- ball of foot on a stair or block)
Crunch
Workout 2
Incline bench press
Shrug
Laterals
Leg X or squat
Leg curl or lunge
Seated calf extension (barbell across thighs, feet on a block)
Twisting crunch
You can alternate these workouts on M/W/F. (Monday= workout 1, Wednesday = workout 2, Friday = workout 1, follwing Monday= workout 2 etc.) or stick with one or the other for a few weeks then switch.
Start with 2 sets of 10 for each exercise for 2 weeks, then go to 3 sets of each exercise, then SLOWLY begin to add weight.
You're "breaking yourself in" to a new lifestyle, take it slow and don't shock yourself too hard. You have to keep this up *for life*.....

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Diet.... I would start by eliminating junk food first. Eat good quality food, don't worry about
portion control until you start to understand what to eat. I believe you will get a great start on the road to being fit if you at least eat GOOD QUALITY FOOD.
If you eat pop tarts for breakfast, stop now.
Replace it with a bowl of oatmeal, a large glass of milk, and a piece of fruit.
If you eat McDeathburgers for lunch, stop now.
Try a tuna sandwich on whole wheat with lettuce & tomato, a cup of carrots, and a big glass of water.
You can see what I'm getting at here....
EAT TO LIVE, DON'T LIVE TO EAT.
Good luck- stop in whenever you need a hand.
Tuna