Many thanks in advance this has been emotional .
On the computer, just go here:
C:\Users\YOURNAME\AppData\Roaming\BitBay
...and replace the wallet.dat file with your backup .dat (rename it back to "wallet" if you saved it under a different name).
You will then have the original wallet's addresses and transaction data. You will also have to use the same password so remember it. If anything, you may need to re-sync with the blockchain to get current but that is understandable.
Scott-
As usual you are a great help and if I was not so all over the place I am sure this would be sorted. I have 2 questions please Scott, when you say (on the computer) am I typing C:\Users\MyName\AppData\Roaming\BitBay into the shell? and when you say replace the wallet.dat file with my back up.dat how do I do that please bud? I found my backup.dat then I left click and I can't find option to replace
to find the correct wallet folder: type %appdata% into start menu search box. that brings up your roaming folder with bitbay inside.
the 'wallet' and 'backup' names can be used on the same dat file, it's just a way of backing up your current dat file (name it 'backup', move it into a new folder in same location) before you put a different dat file as 'walle't for bay to find when it starts up.
hope i have understood your q correctly.