When you live alone, food can be a big problem. You either have to make a recipe that serves 4 to 6 people or microwave a Lean Cuisine... again. Left overs aren't so bad, but it sucks when you have to eat the same thing for a week just because you're alone.
Fresh veggies are a great place to start with single-serve portions because you can buy the just the amount you need and prepare them as desired. Bagged frozen veggies are next best option.
The Hungry Girl cookbooks have great single serve recipes for everything from breakfast to dessert, but they use a lot of processed products in their recipes to cut down the calorie count. Real eggs and be used in place of the fake egg and so on, but that will increase the calories that are listed for each recipe.
Breakfast food is a great option for single-serve cooking, but they are often carb and fat heavy. Which is why cooking it single-serve is great, because you have the treat one day and aren't left with it sitting around.
Cooking for yourself can be hard, but it's one of the best things you can do for your body. Having complete control of everything that you ingest is step one to becoming a healthier person.