How to create a multi-page website with big database?

Hi guys,

I am not an expert web delevoper, but I am working on an interesting project that includes relatively big database, comparisons and needed categorization on the home page. The question is – if it is possible to develop such a page with WordPress and if so, which plugins are necessary to be used?

So here is the concept:
>I am creating a website with some focused comparsions among different tools/products to use (similar than this, just on a local base and with different categories http://www.toptenreviews.com)

1. How could I create all those different categories (20+)?
2. How to make sure that I don’t have to change every single page if I want to make a change on all comparison pages?
3. Is there a way to use hashtags as a categorization?

Any other advise how to start with such a page?

I really appreciate all your feedback!

Best,
Grega