how do i get a recovery disk for an 6 year old Imac

That can be tricky at best. Sometimes AppleCare has them, sometimes it doesn't. A 6 year old iMac though puts the date around 2008-2009. If that's when it was, then you may be able to use the retail 10.6 installer on it, as it was released March 15, 2010. That at least should be able to give you a software that works well with it, short of the custom installed software that came with it. Only upgrade to Mac OS X 10.7 or later, once you have read this http://discussions.apple.com/docs/DOC-6271

Also please note, no 6 year old iMac can run Classic. Classic was available on Macs from 2006 and earlier. Here's where to post n the future:

http://discussions.apple.com/docs/DOC-2463

The first thing you need to do is to identify your iMac better than, "6 year old."

Visit this site and use your iMac's serial number to identify it. I believe that it is printed on the bottom of the iMacs foot/stand.

https://support.apple.com/en-us/HT201300

or

http://www.powerbookmedic.com/identify-mac-serial.php

Contact Apple Support and have the serial number of your computer available. They will send you new disks for a small fee.