Circuit City Quarterly Loss Narrows  CHICAGO (Reuters) - Circuit City Stores Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=CC.N target=/stocks/quickinfo/fullquote"&gt;CC.N&lt;/A&gt; on  Friday reported a narrower quarterly loss from continuing  operations as sales of higher-margin warranties and improved  distribution helped offset weak merchandise sales.