I buy non perishables every two weeks, and just go back weekly for fruit and milk.
We make the list out before the bi-weekly shopping trip and buy all the ingredients we'll need for the 2 weeks worth of meals. Also, I always have one or two ready-made meals for those nights when we just don't have time or energy to cook (no matter how well we plan, these nights happen!): frozen pizza, stouffer's lasagna, chicken viola...you get the idea.
Here's this week's dinner menu:
Monday: Meatloaf, mashed potatoes and green beans
Tuesday: Pork BBQ (in the crock pot) with cornbread pancakes and slaw from Diskey's BBQ (I can't make it that good)
Wednesday: Ham, beans, rolls (other stuff -- we're hosting a party today)
Thursday: Chicken, rice, asparagus (green giant frozen asparagus, steams in the bag)
Friday: sausage spaghetti, salad (the kids won't eat salad the regular way, but one kid will dip fresh spinach and carrot sticks in ranch, and they eat cucumber slices, so their salad is sort of in pieces, and I buy with that in mind...)
Saturday: chicken fajitas with mexican corn and rice
Sunday: roast with carrots and potatoes
We serve fruit with every meal, so I buy fresh fruit, but also keep canned on hand in case we run out before I go to the store again (and we usually do). I stock fruit mainly based on what's on sale, but the staples are: apples, grapes, bosc pears (they're sweeter than bartlett), kiwi (son could eat his weight in them), blueberries, and canned mandarin oranges and pineapple todbits.
Lunches are simple -- sometimes leftovers, often sandwiches or hot dogs (with chips and fruit), chicken nuggets (with green beans and fruit, maybe rolls or bread too). One great lunch idea I got from a friend is to roll lunch meat slices and cheese into crescent rolls and bake them. Kids love them! Of course, when they're at daycare, they take care of lunch!
Next week, the meats will probably be the same, and there's one night we'll eat out, and I try to keep enough vegetables (canned and frozen) on hand that we should be able to make the next week's menu without a special trip to the grocery store. However, since I have to go back anyway to buy fruit, I can pick up any extra stuff while I'm there.