Dummy / Easy to use Photo Size Converter

[CyberNerd]

upload to picassa web albums - it displays them in a webpage automatically resized for sharing

[leon999uk]

For all you Mac people out there, there is an application called iResize that does this on macs and its free!

iResize Download Page

[Slewis]

I'd recommend PIXresizer, (Freeware)

It'll do percentages and pixel sizes for individual images, as well as allow you to change between common filetypes, should you wish to. Also supports batch file processing, read CNET's blurb for more.

[laserblazer]

I used this one for batch resizing - seemed to work ok.

Just installed and it's dead easy to use. It says for Home use only but if you look at the licence it includes education and non commercial.

[round2it]

+1 for this

[jc1875]

Imageresizer on Codeplex

Very similar to the MS one, but works on vista and windows 7
Image Resizer Powertoy Clone for Windows

also allows you to specify custome size.
AND - rolls out via .msi for group policy