Metropol

How do you say on a seperate page to a forum what topics are being discussed?

You mean like how Digital Spy (http://www.digitalspy.co.uk) do it, with a list of forum topics on every page?

Usually done by a supplied program with the forum software which would automatically do it for you.

If you take a look on phpBBhacks.com you should be able to find a mod for it.