I Upgraded to V2 for jfk but did not uninstall V 1 first
The V2 installer won't continue if you don't uninstall V1 first, so it seems strange you were able to install V2 without uninstalling V1 first.
How to I get to my Home folder to make JFK active?
"Home folder" is the standard term for the folder with your user name. The one that contains "My Video", "My documents", etc.
I click on Backup RegKey and get message find in home folder & click on it just gets me flying at airport in fsx
That's fairly normal: the Backup RegKey, doesn't activate anything. As the name suggest, it makes a backup of the serial number of a product AFTER this has been successfully activated. Not that you normally need to use it manually, because the proper function to register your Serial Number, which is aptly named "Register Serial", ALSO does a "Backup Regkey" automatically, as soon the registration is successfully.
So, to register your scenery and make it active as a full version, you use the "Register Serial" function instead, which will ask for your Serial Number, as indicated in your purchase receipt.
About JFK V2, this assuming you PURCHASED the new version, since it's not an upgrade, it's a new product offered with a significan discount to existing JFK V1 users.