You need to keep all the pixel data intact in the document, and scale only at the output (print) stage.
So, don’t scale the image in Photoshop. Don’t apply image adjustments or filters unless you are deliberately trying to alter the appearance of a screen shot. By all means use Photoshop to crop the image, or erase or paint over parts you wish to change, and save in a more suitable lossless format, e.g. TIFF with LZW compression. But never scale it in an image editor because by doing so you are removing vital data (scaling down) or introducing redundant data (scaling up).
Instead, import the screen shot, edited or otherwise, directly into your document processor and use whatever functions are available to your document processor to scale the image. In Word for Windows, for example (ugh, the very thought of it makes me nauseous) I would drag in the screen shot (which I would paste into Photoshop, perhaps edit, flatten, save as TIFF) and scale it to 50% or 25%. This works because scaling in Word means changing the resolution at which it prints, it does not change the image data, even though it looks like rubbish on screen.
set interpolation to nearest neighbour is the best way of keeping the integrity of screenshots when resizing them…but there’s a catch, when reducing you can only do it by 1/2 other wise the pixels dont quite line up and text can look a little odd.
nearest nieghbour will allow you to keep the image intact when englarging…but always enlarge by a round number, an integer…if you end up with an image too large then just adjust the DPI up (while keeping the file size the same, ie dont resample)…thats how its done in manuals.
dont rely on a rip to keep your images at a low res as previously suggested, some workflows can up res images at print stage…you dont want that, they may look like what your trying to avoid.
