For starters skip the bicep curls and calf raises. You're going to want to strenghten as many muscles at a time as possible. Just hitting biceps and calves is pretty much a waste of time if your other muscles aren't pretty well developed.
Weight lifting exercises called compound movements are the key. They hit lots of muscles all at once and help you to burn the most calories. Not only that but the extreme load that they can put on your body also helps to release hormones that force your body to build even more muscle fibers and to burn up even more fat.
If I could only do five exercises for the rest of my life these would be those exercises becacuse they will give me the most bang for the buck when it comes to buildinging muscle.
- incline bench press (personal preference but flat bench is fine)
- bent over rows
- standing military press
- pull ups
And that's it. All of my favorite exercises. By varying up number of reps, rest time, and a bunch of other factors that would be the only exercises you'd ever need to do ever again.
My workout partner does all of these exercises just like I do on a weekly basis. He is just as serious about staying in shape as I am. You can read his story here.
If you don't have a workout partner you should seriously consider getting one. Even if they can't make every workout with you they will keep you honest and motivated. On the days that your schedule does meet up you'll have better workouts as they will push you a bit.
You can also lean on each other to make sure that nobody quits. It's the best way to stay in shape for the rest of your life.