To diet or work out.. or both

As always, I am struggling with whether to diet, work out, take diet pills, or do all three. All I know is that I need to lose weight and get into better shape. I am not over weight but I would love to have more energy and I know getting in shape would help me in that area. It would also give me more confidence when it gets nice out and we want to go swimming with the kids. Now I just need to figure out my plan and stick with it.