You can't do that with the free Reader.
Also, you didn't download it to Adobe Reader, the site must have something that can create a PDF on the fly and it's what is making it two pages. You'll want to contact livecareers with any problems with their procedures.
You can create the same resume in Microsoft Word 2007 or 2010 and save it as pdf file (or printit in Bullzip pdf maker). You have more control using Microsoft Word then using an online resume maker because there is no way to format it to fit into one page.
Hope this helps.