When you right click on a picture it gives you a number of options, size, quality and where you want to save.  It has some other options.

http://virtualgenius.spaces.live.com/blog/cns!CC3C966FA733667C!421.entry

 to go directly to the download page

http://www.vso-software.fr/products/image_resizer/download-image-resizer.php 

I did scan the download with AVG,  Spyware Terminator and A-Squared Free.  All said it was ok.

Tried it out and it worked fine, I took a 1.4MB picture and turned it into a 256KB picture at 1025X768 and put the new picture on my desktop for sending in an email.