Calorie counting is a great idea, Nelie!
You can choose the foods you like to eat, just try to make wiser choices (fruit instead of candy, as many veggies as you can, avoid fried foods, etc). Just measure or weight them and keep track of the calories. It's probably the easiest diet to stick to. The best thing is that you are in control and you know what you are getting
If you want something that is laid out for you, I agree with nelie that the South Beach diet is a good one. Our SB forum has the lists of approved foods, as well as tips for sticking with it and loads of recipes. You can read about it and decide if it's for you for free