yes it is I would recommend optimizing title tags, you have website name -> page name its better to have page name -> website name good luck
well there are several guidelines, for urls with keyword - that helps seo, also semantics etc. you can read more about seo at seomoz.com/blog
Yep I would agree with that. You need to use separate descriptions and keywords for EACH page of your site. Also, using H1 tags to identify the topic of the page is good. Since you are using Joomla I recommend downloading OpenSEF instead of the SEO mod you are currently using. It has a built in feature that will auto generate meta keywords and descriptions for each page that is really cool.
Title Tags and Index page keyword relevance are very important, make sure these are all in line with each other.
For the sake of brevity you could head over to my blog hxxp://www.oscandy.com and do a search for search engine optimization. This is not a shameless plug. I am a Joomla developer and run socioclick.com for social media extension. Just converted the popular wordpress landing page to a Joomla module. The up and coming Joomla templates are a hindrance to SEO due the manner the scripts are developed with SEO in mind. For one I would go with the post for OpenSef to be implemented and second I would use Joomla SEF Patch extended at joomlatworks.com. Feel free to drop me a line