I commend you for setting goals for yourself, most people who are overweight just complain about it and never even make it as far as you. Great job in that! Cutting out sodas and sugary drinks is a great start; you might also want to look in to raising your lean protein intake and lowering your carb intake (esp. fast carbs). As far as a workout goes I think that you would have great results with basic circuit training and cardio.
Use the following for the summer and you should lose your weight and tone up considerably (as long as you keep your diet in check that is :
Day 1: Medium to Low intensity cardio- 35 min. This means to keep your heart rate at 120-140
Go through the following exercises without resting in between then repeat for a total of 3 times through:
Dumbell Bench Press x 20
Dumbell Curls x 20
Barbell Deadlift x 20
Dumbell Overhead Press x 20
Barbell Squat x 20
Lat Pulldowns (Wide Grip) x 20
Day 2: 40 Min. Cardio
Day 3: Rest
Day 4: 45 Min. Cardio
Weightlifting cirtcuit x 3
Day 5: 45 Min. Cardio
Day 6: 45 Min. Cardio
Circuit x 3
Day 7: Rest
Vary the types of cardio you perform every day, ex. biking, swimming, treadmill, basketball, elliptical, etc.
You can also vary the order of the exercises in the circuit from week to week.
As far as supplements go, I wouldn't worry about anything except mabye a protein powder. Whey protein is a very versatile protein and can be used to replace meals or as a post workout recovery drink.
The key is consistency, if you want to meet your goal then make it happen. Don't miss any days. Just keep you goals in mind and work hard and you will be amazed with the results. Good luck,