Morgan, in photobucket you need to go into the picture (so if you are looking at multiple photos on your main page, click on the photo that you want to edit) then click on the resize link which is just above the picture on the top left, it gives you a few options, however if your photo is already small it won't let you resize it. It should change in size once you click the size you want (it takes a second and reloads the page), oh and it pops up a little tool tip to ask you "are you sure you want to resize this photo" click "yes" and then use the img code to post it here.
Does that help at all?