Betty Crocker -- of course!
Joy of Cooking
How to Cook Everything (good for vegetables, pick up fresh vegies at farmer's market without a plan for it.. check book for ideas)
Dad's Own Cookbook.. very basic recipes, time tables, basic how to's, nutrition. My DH picked it out years ago and we use it frequently.
My newest find:
Saving Dinner .. they have a website too.
http://www.savingdinner.com/
Haven't dedicated myself to it yet, but it sounds workable for most families.
For vegetarian meals I use:
The Meatless Gourmet, Favorite Recipes from Around the World
Easy to follow, not too weird of ingredients. Very believable meals and have dishes that meat eaters would like too.
If you find old cookbooks at thrift stores and garage sales.. scoop em up! I have some great hardcover books on making bread, cookies, and a really old version of Betty Crockerwith nice frugal meal ideas and how to's on baking techniques.
And yes.. some of these collect dust due to recipe web sites.
I stopped buying cookbooks.