So what we have now, is a folder of high quality pics, that have been cropped and renamed, but are still too big for the web. So now we are going to make smaller copies, and then rotate any that are on their sides.
Open Irfanview, and open the Batch conversion tool, by clicking on File/Batch Conversion, as here;
You will now see this screen;
Now click on the 'look in' box (A), and browse to the folder with your picturess. Click on the 'Add all' button (B), and you will now see the pics listed on the left.
Click on the output directory 'Browse' button (C), and choose the new folder you made inside the pics folder, the one I called 'for web'.
Now click on the 'Use advanced options' tab (D), so it is ticked, and then on the 'Set Advanced Options' button.