I use Roxio Photosuite v. 6 to resize pictures... and ver. 5, which I actually like better in most ways, doesn't have the resize option. So not all photo manipulation software does.
When I want to play with a pic, I save it to the computer, usually through the right-click-and-save procedure that Hobby just mentioned, or I scan it or download it from my digital camera.
With the scanner pic or digital pic, the picture always needs to be resized.
So I fire up Photosuite, import the pic in question, resize it, and then resave it to my hard drive.
If it's for the avatar, I load it up straight from there.
If it's for the sig, I fire up Photobucket, load up the pic, and just copy and paste the img pathway that photobucket provides for you.
It's not an easy way to do it, but I can't think of any better way.
Speaking of posts which haven't been answered, Miss Wonder Woman (and that IS an impressive bust, there, girlfriend), , did you see that your question about where the name b77 came from is in the Guide to b77?