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.
· 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!