Can someone point me to an example of how to implement the following
type of application inside WSS 2003?

I would like to be able to link tasks to requirements. The catch is
that that a task could be linked from 0 to N requirements.

For example, here are three tasks and three requirements.

Task 1. Design a webpage layout for home page.
Task 2. Chose a database for website backend.
Task 3. Chose a Hardware to host the web front end.

Req 1. Design for 1000 concurrent users.
Req 2. Average page load under 1 sec.
Req 3. Provide full text search.
Req 4. Navigation should be on top of page.

In this example,
Task 1 is subject to requirements 1-4
Task 2 is subject to requirements 1-3
Task 3 is subject to requirements 1-3

I really have two questions.

1- how to link the lists (assuming that is the right approach)
2- Best way to create a GUI