I use a free program called PhotoReize400.exe that is both versatile and very simple to use. After installation, you have an executable program called something like PhotoResize_WxxxHyyy.exe where xxx and yyy are the number of pixels Width and Height you want the resized image to be. You can change xxx and yyy to be any value you want, I keep half a dozen or so copies of the program with commonly used values already defined. To resize an image, you just use Windows Explorer to drag the file onto the PhotoResize_WxxxHyyy.exe file, and it resizes the picture to the xxx by yyy specs and puts the resized copy in the same directory as the original file with "Wxxx" appended to the original filename.