Evaluating Images for File Compression

Fireman Fish Bowl Jack in the Box Barney Marin Logo
Click images or links to see larger images.
To put these images on the web, I reduced the dpi to 72 (some, such as the fireman photo, were at 300 dpi).
Also, I reduced the pixel size to 120 pixels wide (to fit them across the page).
Finally, I used Photoshop's "Save for Web" option. I accepted the image Photoshop said was optimized,
even though the entire point of this assignment was to fine tune it even more!
Here is my evaluation of the images, and response to the challenges of optimizing them.