You can get 2-3 weeks out of oranges and other citrus fruits especially if you refridgerate them. Since they don't continue to ripen once removed from the tree they will remain roughly the same quality and flavor until they mold. Just pay attention when buying them and make sure the outside is in good condition with no scratches, tears, or other marks as that will speed up the molding process.

Other than that, that's about all I can think of along the lines of fresh fruit that will last any length of time.

Potatos, onions and garlic all have a shelf life of atleast a month and if you are careful in the grocery store you can often find eggs that will be good for 3-4 weeks from purchase date. With those four things you can throw together a pretty good breakfast of eggs and home fries and of course you can eat breakfast anytime of the day. And I've never really looked at the pre-processed egg things but I think those may have even longer shelf lives than fresh eggs.

Any type of fish will freeze incredibly well and defrost very quickly. Lemons, fish, rice, and a few herbs and you can put together a really healthy dinner with ingredients that will last last atleast a month and are incredibly inexpensive so even if you throw it out you're not out a lot of money.