One of the most essential tools I think you need is the Image Resize Powertoy, now this currently only works with Windows XP, but after much searching around, I found one that does the job just as good as the one made by Microsoft, except it works with Vista.
The Image Resizer for Vista is a must have for anyone that is missing the Powertoy from XP that allows you to quickly resize an image from the context menu. Unfortunately it isn’t compatible with x64 Vista as of yet, but is currently being tested. If you run an x86 version of Vista, you can download it over on the download page.
Update: The Image Resizer has been updated to build 2519 and now also has x64 support. Head over to the download page to grab the new builds!