As a commenter already said, pretty much anything can be frozen and will last. The real question is one of resemblance to the original pre-freeze food. Uncooked meats, butter and liquids (bone broth and such) suffer the least from freezing, while foods like raw fruit and vegetables, unprepared herbs, and oils can change drastically. The main reason is ice crystals and thermal separation.

Thermal separation first. All oils (or at least paleo oils like olive and some nut oils) have a water content. Water freezes at a lower temperature than fat, so the oils tend to separate and make thermal strata in the vessels they're frozen in. This is less a problem with butter, as the water is generally more "worked into" the fat matrix than traditional oily fats. I avoid freezing all oils, but will freeze butter after a 24-hour stint in the farthest back (i.e. coldest) part of the fridge.

Fruits, vegetables and undried herbs tend to have a very high water content, while Protiens have a proportionally lower water content. As ice forms, it creates jagged crystals thst perforate cell walls. This is particularly problematic for items with high water concentrations like berries, apples, and the like. To further complicate matters, the longer a food takes to freeze, the larger the ice crystals, and the bigger the lacerations into the (water-retaining) cell walls of the target food; and that's why berries and bananas are really mushy when thawed after home freezing. Meats suffer the same fate, though less dramatically. I always chill my meats for 24 hours in the coldest part of the fridge before moving to the freezer to reduce ice crystal formation; I also use a vacuum sealer to remove excess air to prevent freezer burn.

Based on your question, I'm unsure if you want to run a "freeze all the leftovers" or "partially prepare easy to cook meals" route. If it's the former, be aware that all of the components of a meal (think meat, vegetable and sauce) are going to freeze quite differently, and will probably give you less than desirable results. However, if you want the Paleo TV dinner, you're in luck! Many main-course recipes can be easily adapted to be partially cooked, then chilled and frozen. I'm of the opinion that vegetables should be frozen by professionals, or skilled amateurs who are comfortable playing with liquid nitrogen, so those are cooked as needed. The protiens, however, can be partially cooked and frozen a majority of the time.

In addition to Blitherakt's excellent response, I would add that I personally wouldn't bother freezing raw fruits and vegetables at home, since they are sold already frozen, and this is one form of processing that food producers seem to get mostly right. Frozen produce is often fresher and better quality than fresh, since it's frozen soon after harvesting, instead of being trucked across the country, losing nutrients on the way. The money I save on wasted produce I never quite finish justifies the cost of frozen organic stuff.

But if you insist on freezing your own raw produce, or stumble into an unbeatable bargain and want to stock up, then learning to prepare them for freezing is a must. Google "blanching vegetables" for numerous instructionals. Almost all fruits and vegetables should be blanched prior to freezing to deactivate enzymes that cause decomposition. Some fruits are okay to freeze without blanching, and regardless, fruit suffers the most from the effects, so you'll use these mostly in blended or cooked things, like sauces, smoothies, baked goods, etc. I can't think of any frozen vegetable that I use without cooking, though they aren't as mushy as fruits.

Freezing things that have already been fully cooked is most successful, since cooking also causes that cellular breakdown. There is almost nothing I won't pop in the freezer. If you're worried about wasting food, and the alternative is to pitch something, go ahead and freeze it as an experiment.

• I always store flours and nuts of any kind (whole, toasted, raw, ground) in the freezer because I don't use a lot of them, they're expensive, and they go rancid easily at room temperature.

• I freeze butter, and never bother with the precautions mentioned re: chilling thoroughly first, and I've never had any trouble with it.

• Unless you live near the water where it's caught/harvested, nearly all "fresh" fish has been frozen before coming to market, then thawed for presentation and sale. You can generally freeze it once more before cooking, but if you're planning to freeze it anyway, just buy it still frozen instead of "fresh." Once it's cooked, you can freeze it again, but like any prepared fish, it's best consumed right away and it's taste and texture can suffer after cooking, freezing, then reheating.

• Many high-moisture leafy herbs (like basil, parsley) will suffer the same textural deterioration, but you may find they still taste better than dried herbs. Dryer herbs like rosemary, oregano, thyme won't be as mushy, but still, like vegetables, plan to use your frozen herbs in cooked foods for the most part, and perhaps dressings/sauces.

• blueballoon's answer discusses an important technique: freezing small things spread out on sheet pans before bagging up your stuff for storage. You do NOT one want a 1-pound solid frozen block of broccoli ice. It will be impossible to cook properly, and you'll have little choice but to thaw the whole thing, regardless of how little you need.

• A zero-degree (or below) deep freeze/chest freezer that does NOT auto-defrost is best for long-term frozen storage of anything. The defrosting cycle in your fridge is the primary culprit for freezer burn, because it uses a constantly repeating freeze-thaw cycle that ruins food pretty quickly, and no amount of plastic protects from this.

• You can freeze food in glass canning jars! (Wide mouth jars only, though!) Most people are justifiably nervous about freezing in glass, but wide-mouth canning jars are designed for this. Leave plenty of headspace at the top to accommodate the expansion of liquids. These are great for soups/stews, and you can reheat in the jar, then eat out of it, making it handy for weekday lunches at work. It's also very easy to get frozen stuff out of wide-mouth jars: run under warm water for a moment (or set it out on the counter for a few minutes), tip, and the whole lump of frozen stuff drops out. But keep in mind, it is glass, so it can break easily if you drop it, or bang it into other jars in the freezer too hard.

I don't have the freezer space to do much in the way of fruits and veggies, but I've found that it's fairly easy to get good results when freezing raspberries, blueberries, and blackberries. Freeze the berries on a large cookie sheet, then transfer to freezer bags or other containers. (I use Pyrex containers myself.) Herbs are relatively easy as well, although I think drying is better/easier with herbs. (Tie them up with string and allow to dry in a well-ventilated place, then store in an air-tight container.)

As for meals, you can do a couple of things. First, you can just freeze leftovers. Stews, soups, and chilies freeze very well. If I come into a lot of produce and other soup fixings I'll make a huge batch and freeze half of it in meal-sized portions. I find, though, that it's easier for me to feed the kids and myself leftovers throughout the week than to freeze half the batch for later. The second option--what I do most often--is to make a batch of something specifically for the freezer. For our family this usually means a big batch of beef stew or chili. I'll portion it out into several containers that hold enough for a full family meal. Then I have a few 'emergency' meals for when I really don't want to cook, and can't afford takeout or a restaurant meal.