No, it can't extract pages because Adobe Reader XI is not the same as Acrobat, the application that edits PDF files. Reader will only allow you to open and browse through pages, but luckily for you, there is a simple way to do this.
You can Print to PDF from PDF using a virtual printer. Access the website listed below and install CutePDF Writer. Once it's installed, restart Adobe Reader and open the PDF file. Go to File > Print and then select the CutePDF Writer. Choose the page you want to extract by typing the page number in the select box under the Page Range. A dialog window will appear asking you where to save the file.
Download CutePDF Writer: http://www.cutepdf.com/Products/CutePDF/writer.asp
Note: Internet connection is necessary to complete the Writer's installation procedure.