A running program is always a good way to build up overall conditioning. Running two to three miles three times a week should be more than enough to help you get into condition. However, don't start off by running that much distance. Instead, start off by running 1/2 mile. If you can run on a track at a high school or a college, 1/2 mile would be two full laps. Start off slow, but try to run hard the last half of the second lap.
Build strength by getting on a weightlifting program. Using free weights like dumbbells and bar bells will help you build strength quickly, but you will need a spotter to help you with the equipment. If you don't have an opportunity to work with a spotter, using Nautilus exercise equipment will help you build up your strength. The Nautilus machines operate in circuit and allow you to work on your upper body, core muscles and lower body muscles.
Build strength in your core muscles by using an exercise ball. Sit-ups done on an exercise ball are far more effective than those done on the ground. Sit on an exercise ball and find your balance point. Lean back while keeping your feet on the ground. Lay back on the ball, and then lift your head and neck about 12 inches. This will work your abdominal muscles.