I suggest you spend some time reading Sheldon Brown's tech articles. (Just google the name; he has dozens/perhaps hundreds of pages that are linked from the Harris Cyclery website and vice-versa). Focus on his explanations of wheel sizing and frame spacing. Read up on chain line, too.
You might have different diameter rims among the three bikes. This doesn't necessarily make them incompatible, but it's an important consideration. Hubs can be respaced pretty easily if you're going from a narrow hub to a wider frame. Regardless of whether a hub is too narrow or too wide for a given frame, it might still work, as long as they're close.
Moving a fork from one frame to another is sometimes very straightforward, and other times not possible. Usually it's not worth the trouble, unless you have a good reason for the change. Chances are, your Peugeot and your Raleigh both came with 1" threaded steering columns. I think the Kilo TT is 1" threadless = not an impossible swap, but will involve replacing the headset.
If you have a specific question about one particular change that poses minor technical challenges, I believe someone here will be able to help you. But your "predicament" seems both more broad and more vague than that. Therefore, I repeat my advice to spend time studying the vast treasury of info already published online. Aside from that, here's what I'd say:
1. Pick your favorite bike and put good wheels on it. If it already has some, you're set. If not, save up enough dough for some nice ones. What happens to the other bikes should not play into this decision. Those Vueltas are not bad, but not great. (I've never ridden on them, but I examined some in person. They were just meh.) Velomine and Retrogression both have some really nice wheelsets for $300 or less.
2. If step 1 above frees up some wheels that you can use on another bike, do so (might require respacing). But if you now have wheels that are no use to you, donate them to a bike collective, sell them on Craigslist, throw them away, or give them to a neighbor kid to play with.
3. Pick your next favorite bike and repeat step 1. If you don't have enough money, put the project on hold for a while and accept that you're not meant to have that many bikes at this point.
4. Continue this process until you have three or more bikes with good wheels.
I know what you're going through, because I have five bikes and at least seven or eight wheelsets. I've shuffled them around a lot, and done some respacing to make them work. I learned a lot through this process. Not criticizing you for asking advice, but I think you'll learn far less here than by reading Sheldon's articles, and less from that than by taking out some wrenches and experimenting.