Regarding food storage in buckets:

Not all 5 or 6 gallon buckets are equal. You cant use the crappy ones you'd find at home depot and expect them to be truly air tight. I use 6 gallon buckets from Emergency Essentials which cost about 6 dollars each. Then again I live in UT so this type of thing is easy to get around here. They have a rubber gasket in the lid and a rather thick wall.

For best results you can get big mylar bags that go inside the buckets and block oxygen even better than the bucket alone. They require a big heat-sealer bar.

For sure always drop in some 02 absorber packets.

My understanding is that brown rice does not last nearly as long as white rice. I always put a big salt container right in the bucket. For me a bucket of rice costs about 30 dollars, weighs about 48 lbs (6 gal) and should last beyond my life time. One bucket of rice will feed you for a month. You can add rice to anything to make a small meal a large meal.

Since I have a lot of rice I also get seasonings (big containers) at Costco. You can get cheesy broccoli sauce mix, Mexican and Italian, chili powder etc and you'll make that rice a lot more tempting. The stuff is cheap. You might even throw it in the bucket before you hammer the lid down.

Sometimes doing it yourself is worth it, sometimes not. Somebody mentioned the Mormon canning stations. East of the Mississippi they only sell pre-packaged stuff, but on the west side they still let you use their canning machines yourself. In the end I generally get the pre-canned stuff from them. Don't worry-- I'm not a Mormon and they're perfectly happy to do business with me. They're just happy to see someone come and use the service. Their prices CAN NOT BE BEAT. Get canned dry beans, sugar, spaghetti, etc but don't expect gourmet freeze-dried raspberries etc.

Speaking of freeze-dried raspberries... For a beginning prepper who has some storage space, start with rice and beans. Its not fancy but it'll keep you alive. Start adding 'recipe' stuff later and then start adding comfort foods last.

Rule of thumb regarding food lifespans-- If it has oil in it it tends to do poorly. I don't care if its freeze-dried. A peanut is not going to last-- It'll go so bad you could kill rats with a single peanut after a few years. Anything powdered has a lot of surface area and thus a lot of oxidation is going to happen if you don't keep the air out. Someone mentioned vacuum-seal-bagging machines. I have one and they work well, though 'pokey' things tend to need to be double bagged. Give the items you seal a few days to see if they leak before putting them away. Don't consider the vacuum bags to be good enough on their own, though. I'd still put the stuff in mylar or a bucket or something.

Wheat. Do you have a grinder and do you have the time/oven and fuel/skills to make bread? It lasts forever but its an item that takes time to prepare so don't over-do the wheat.

How much do you need? The answer is related to how much space can you make. Put it this way... Lets compare "shit hits the fan" to the French Revolution. If you started with a 3 year supply, once you ate it all you'd still have 20 years of hell awaiting you before the return of normalcy. And thats imagining that you manage to keep it to yourself top secret and you don't white-knight the food away in the first few months. Thats a whole subject worth talking about.

Even if you don't believe in Mad Max apocalypse scenarios, consider this little made-up story: Your dad gets a letter saying that the family's ration cards are going to be cut in half unless the family comes up with 2 able males between 18 and 45 to go to the Nebraska work-farms. But you have food so you're fine with a half ration card. The neighbors send their men off, but the buses never make it to Nebraska and divert to Texas. You find out that the men are quickly put through basic training and loaded onto ships destined for the latest greatest war. Suddenly those cheap buckets of rice seem pretty damn valuable, eh?