You can use IrfanView to optimize and convert your images.

Go to the IrfanView site and download IrfanView. It's an extremely valuable graphics tool. What you do is load your image into the program, press CTL-R to resize it, change the width parameter to what you want (the height is automatically adjusted) and then "Save as" but before you resave it using a new name, click on "Options" and set the "Save Quality" level to a small number. I used "37" and this reduced the file size down to 34Kb.