Best performance for searching on landing page set criteria

I have two SQL2005 tables:

• Table 1: LandingPages

• Table 2: Products

The LandingPages table manages the heading, description and other details that are displayed on each of about 200 targetted landing pages. Each record also has a set of default Criteria fields that specify what products should be shown on each individual landing page.

So, a landing page about widgets with red tops and blue bottoms would have a record thus:

• LPID: 1
• Title: Widgets with Red Tops and Blue Bottoms
• Product Category: Widget
• Top: Red
• Bottom: Blue

Each landing page record has a unique ID, called LPID.

I want a stored procedure that takes the LPID, reads the criteria and then returns a recordset of matching products.

What is the best way to achieve this for performance?

I have tried reading the various criteria into lots of variables, then doing a select using the variables in the WHERE of the SELECT.

I am trying to see if a CTE can be used / is better than my current method, but I'm not sure I can use the CTE within the WHERE of my SELECT.

-- Extra note: certain options can be changed by the user, such as maximum price and sorting.

Can anyone help? Thanks.