Hi Karen,
I hope you found your answer in the link provided by
jephree Lots of info there

As a note of interest:very often ,clicking or double clicking on a reg file will not give any results.
The reason is that on a lot of systems the reg extension has not been properly associated.
Instead,r-click the file and select "Merge" from the menu.
You will then be asked if you want the contents of the file to be merged into the Registry.Click OK.That should do it in most cases.