I think there is nothing to doubt regarding this issue you need to generate different meta tags for each pages. So don't get confused.
Let's be clear: Each page should be unique - as much as possible of we're talking SEO -- or even usability. This goes for visible content and most definitely for meta data. Your meta descriptions should be written as unique as possible for each page and be written so they will encourage someone to visit your site. Always have unique titles and descriptions. If your titles all start with the same keyword, you end up self-cannibalizing your own site. The same goes for the descriptions are the same, the end up cannibalizing each other.
As most of the users said,i think it`s safe to use different meta tags for different pages.I suggest you to use joomla,they have a nice thing that helps you create metatags easy for every page
All pages of your site should have it's own unique meta description, or you'll get warning in your google webmasters tool's page.
Meta tags are generally meant for the pages contents.so you can proceed with the different meta description for the web pages.But it should be relevant with the page content.So that search engines will get your site in top listings.