Setting up Menus

I have a question of approach on how to do advanced menus in Drupal. I have gotten basic menus to work great and have installed the Nice Menu module which provides great functionality. However, I still cannot figure out how to do something that in other frameworks I have used is ease to do. What I need to do is have the primary links at the top of the page and then have a sidebar that changes with sub-pages under each primary link page. For an example see the site www.planyourlegacy.com (not the homepage, but the sub page behavior). Basically the primary links at the top are About | Products | etc. and when you are in the About section there are 3 or 4 pages of content and a left navigation bar to browse through these pages. Ideally I would like to deactivate or highlight in some way the primary menu item to tell the user what section they are in, but this isn't a requirement.

I have two proposed solutions, but neither seem elegant or easy to do - there has to be a better way: -)
1) Create a taxonomy term for each section and then create a Nice Menu for each sub-section of the site. Set each menu to only be displayed when a page with that taxomomy is being viewed. The way I see to do this is to write custom PHP code (not sure exactly what this will be, but it doesn't seem to hard) in the configure block page saying "Show block on specific pages:". This seems very redundant and not like a great solution....also it limits the number of page sections since you can only have so many Nice Menu's.

2) modify the Nice Menu module to do 1 in a more seemless manner - set any . Since I am only a beginner at module development I am not crazy about this option.

Is there a better way to do this? It seems like something that is very standard on websites and yet I cannot figure out how to do it easily in Drupal. Any help would be appreciated.