Image Editing (Picasa)

Two things you should know about Picasa:
Picasa does not store the photos on your computer.
When you open Picasa, it simply looks at the folders on your computer and displays the photos it finds. It displays the file types that you tell it to find, in the folders that you tell it to search.

Your original photos are always preserved.
When using editing tools in Picasa, your original files are never touched. The photo edits you make are only viewable in Picasa until you decide to save your changes. Even then, Picasa creates a new version of the photo with your edits applied, leaving the original file totally preserved.

Google Picasa is the image and movie organizer and editor for Windows and Mac OSX (Intel processor). 
From within Picasa, you can upload images and movies to a web album.  You get 1 GB of free storage.  5 GB is $5 a year.

Image Resizer

Reduce image resolution by right mouse clicking on files from desktop.  Can set to replace files, or add files, with a lower resolution.  A suffix is added (e.g. the term "small") to each file name so you know it's the lower resolution file.

Image Resizer for Windows XP - Microsoft PowerToys
Image Resizer for Windows Vista and 7 - Open Source

Fun with Images Sites

Big Huge Labs - ceate calendars, puzzles, "official" name badges and more.

Photofunia - Use Photofunia to create writing prompts.  Over 100 different designs, insert photos and have fun.  Be sure to check: "Do not publish the photo in Faces section of the website."