It appears you purchased without trying the software first only to find out that your computer does not meet the system requirements for the software. System requirements | Adobe Photoshop Elements
Unless you have plans to upgrade your system, your best hope for the moment is to pursue getting a refund.
Please see Return, cancel, or exchange an Adobe order -
http://helpx.adobe.com/x-productkb/policy-pricing/return-cancel-or-change-order.html
Chat support - For the link below click the Still Need Help? option in the blue area at the bottom and choose the chat option...
Make sure you are logged in to the Adobe site, have cookies enabled, clear your cookie cache. If it fails to connect try using a different browser.
Get chat help with orders, refunds, and exchanges (non-CC)
http://helpx.adobe.com/x-productkb/global/service-b.html ( http://adobe.ly/1d3k3a5 )