I cannot give you all the answers to your questions but in my opinion Joomla! is no better or worse than any other CMS for
SEO.
I have hosting on godaddy with joomla installed and one of my sites have over 300 pages indexed after 12 months. Like any other sites, you still need to do the
SEO work and try to get the back links for top placement.
New
SEO | TOOLS | Tricks tutorials: http://toptenseotools.blogspot.com/
Managing joomla! is a little tricky for a beginner and I suggest blogspot with its own build in wysiwyg editor + it's free!