How To Install The Beneath A Tranquil Sea Screensaver
Download the zip file and unzip to a scratch directory.
Copy the files BeneathATranquilSea.scr and BeneathATranquilSea.DAT to your winnt/system32 directory. "winnt" may be called "windows", and "system32" may be called "system" on some older computers.
Right-click on an empty area of your desktop, select "Properties", then "Screen Saver", and select "Beneath A Tranquil Sea" from the drop-down menu. That's all!