Yes, you can mix meals from different menus. You can also make your own menus from scratch so the recipes are easier or more convenient -- or whatever. What's important is to have a variety of foods from each of the food groups, and to come in close to the recommended amount of calories and fat for your level.
If you like you can also use the Exchanges to plan menus. They are groups of foods that contain relatively the same amount of calories and fat per serving. Section 5 of the Healthy Eating Guide contains a list of the Exchanges, and there is a chart on p.18 that has a chart of the number of servings from each group at each calorie level.
Please let me know if you need anything else.
Pat Baird, MA, RD, registered dietitian
Pat Baird, MA, RD, registered dietitian