well, what app will you be laying everything out to? That will determine what format you'll wanna use image-wise. I'm very happy to hear you had the originals to work from - that makes things for you much easier... because not only will you have to convert the color, you'll have to modify the "header" of the image, per se, for print. Digital cameras save images as "72dpi" (it's a misnomer as it's really PPI and not DPI - DPI=dots per inch... there are no dots in a bitmap, only pixels, so PPI is "more correct", but people use the terms interchangeably - not saying that is correct, but people will and I'm just mentioning that as a bit of triva
Depending upon what your printer needs, you will need to resample the images to a new DPI/PPI setting. Generically, we'll say they need to be 300dpi (i'll just use dpi from here on to save typing). In other versions of PP, it's Image/Resample and you can enter in a new DPI setting... but make sure you have the checkbox marked for "keep original size". That's very important. You're not really resampling as in physically making the image larger or smaller, but you're telling the app you use to lay this stuff out in what the physical dimensions of the image are.
For example, make a new file in PP that is 300x300 pixels in size at 100dpi/ppi, choose whatever color you want for it, and save it (CPT format). Now do a file/save as and give it a new name and recolor the image. Then resample it and tell it that it's now 300dpi/ppi and tell it to keep the original size.
Import both files into Draw but also keep them open in PP. In PP, you'll see both files are the same size - that's because PP doesn't care what your dpi/ppi settings are. It only cares about the actual number of pixels for height and width. Draw, however, will look at not only the height/width in terms of amount of pixels in the image, it also looks at the file's header which tells it how many pixels are supposed to fit in a one-inch line (or centimeters, etc). Your 300x300px images in Draw will show at 2 different sizes. One will be 3-inches square and the other will be 1-inch square.
So, what app will you be doing your layout in? Are you using the full version of Acrobat to make your PDFs (or some other 3rd party converter?)?