trouble with sideboxes

i have added 2 side boxes...with 2 separate images and 2 separate url links.

first question...how do i change the title of one of the side boxes...one currently says "Sponsors" and i want to change it to something like "Newsletter". is this changed in the admin panel or somewhere in an ftp file?

second question...everytime i refresh the page, the side box images switch between boxes...sometimes, it will have 2 of the same image and link and sometimes one of each....i know that sounds weird, but i don't know how else to explain it.
you can see what i mean here: http://twinmomscraps.com - they are on my right side bar...if you refresh a few times, you will see how they change and are NOT constant.
i want the 2 boxes to work completely independent of eachother...i know this has got to be an option, but i can't figure it out!!!
please help...thanks in advance.
rebecca