39, just the one kid. Wife goes to the gym in the mornings, I go in the evening. I'd prefer to do morning because I'm way more productive in the gym when it's early...but the wife pretty much won't go if she doesn't go in the morning. I do a mix of strength training and cardio, cardio in the way of circuit training...I have hated running outside the playing of a sport for my entire life, but circuit training gets your heart pumping and it's not boring. I can work up a sweat much better doing circuit training than getting on any piece of cardio equipment at the gym, and you can build in a ton of variety.
To us the biggest thing is having an agreed upon schedule, you each know when you go, and your responsibilities while the other is working out. I have a decent setup in the house, but I prefer to get out of the house to workout, change in scenery is good.
Regarding taking weight off, and keeping it off, no one can out run or out lift a bad diet. To me the best thing is to just start getting rid of the junk gradually. If you get rid of sugar and other simple carbohydrates your physique will improve. As an adult I definitely understand it isn't fat in your diet that's the enemy, it's simple carbohydrates.