if you mean resizing your images to smaller or larger sizes..... then VSO ImageResizer is for you: http://www.vso-software.fr/products/image_resizer/ or there is another free program, Faststone Image Resizer: http://www.faststone.org/
I use adobe photoshop elements 4 or adobe photoshop CS3..... both cost money.... but by resizing them to a smaller footprint, say 800 x600 pixels..... that would be a good size to send in emails. use the free programs above and check it out.