No idea on the Sip, I'm afraid.

installing rootsh doen't make your phone more available to anyone than it was before, I think. When you instlall the ssh server software you will be asked to change the root password (or at least I was) and you should do this.

Still, there is no harm in changing it right now!

regards the images directory, I don't have that on mine .. Can you show exactly the output of

while in the Mac OS directory?

There is a .images directory in /home/user/MyDocs, btw, which can be confusing in that it won't show up in the output of ls unless you use the -a switch, but it does show up as "Images" in the file manager...