McDonald's Same-Store Sales Rise 6.1 Pct.  NEW YORK (Reuters) - McDonald's Corp. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MCD.N target=/stocks/quickinfo/fullquote"&gt;MCD.N&lt;/A&gt; said Monday  that sales at its namesake hamburger restaurants open at least  13 months rose 6.1 percent in October, helped by a popular  Monopoly game promotion in the United States.