Forget using photo-printing software and simply use Microsoft Word (or something similar, such as OpenOffice Writer). Somewhat surprisingly, it's often simpler!
Open a new document in Word. Go to Insert > Picture > From file. Navigate to the location of your 1st image and double-click on it. It will now appear in your Word document. Resize it by dragging the corners or, for greater accuracy, right-click on it and select 'Format picture', which will enable you to select precise dimensions.
Hit return a couple of times (so that there will be a space between your images) and repeat the procedure for your next image, and so on.
Easy peasy!