If you want a tool that will be used simply to resize your existing images, then take a look at this outstanding free one:  PixResizer  (for Windows only)

This program is extremely easy to use...

Step 1 -- First be sure to make copies of any pictures you want to resize, so you will have your original masters as a backup;

Step 2 -- Download "PixResizer" from the link above;

Step 3 -- Setup / launch the program.

Instructions:

   · Load the picture you want to resize;

   · Click the "Custom Size" -- make sure that "Maintain Aspect Ratio" IS checked;

   · If your picture is wider than it is high (landscape view), then set the first field to 410; however if it is higher than it is wide (portrait view), then set the second field to 410;

   · Select JPEG;

   · Do NOT check "Output Gray Scale";

   · Click "Save Picture" button;

   · You will need to give the image a new name, also, select the folder for saving.

   · That's it!