Bonnie - I haven't used this particular key, but I have used REGEDIT a lot. When you run it it will look a bit like a Windows Explorer window with the keys in the left hand pane. Move to the subkey given above as if you were moving to a folder in Explorer (ie Click + to open subfolders, - to close them). When you get to the subkey, do what it says - right click in the right hand pane and you will get a context menu with New on it, then that will open with a set of choices and you should choose DWORD, it will create an entry on the right with a generated name highlit for you to edit - just overwrite it with the text: EnableBallonTips. Then double-click on that name and a box will pop up for you to enter a value - 0 as given. Then exit Regedit and you're done, apart from having to log out and log back in to enable it. The warnings relate to the fact that there's a lot of sensitive stuff in the registry that you mess with at your peril, but if you're careful you'll be fine. (You can save the original keys to restore them later, but not worth it here).

I hope you read the part about this change disabling all balloon messages, in particular notifications for critical updates (if you have that enabled) will not appear - you'll need to check for Windows updates manually.

If you don't like the change, you can use Regedit, go back to the key, highlight your new EnableBalloonTips entry in the right hand pane and delete it - you'll be back where you started.

Mick