Originally Posted by Brian Carlton

Firstly, all of your important sites should probably be in the Firefox bookmarks. The shortcut simply directs the machine to those bookmarks. You can easily recreate the shortcut back onto the desktop from the bookmark.

However, if you saved the shortcuts somewhere in "my documents", you'll be able to easily restore the shortcuts to the desktop after the reinstall. But, first you'll need to go and get Firefox and install it. Then, you'll need to get the bookmarks and restore them. Finally, you restore the desktop shortcuts and they should properly work with the reinstalled bookmarks.

It's a bit of a process when you do it for the first time.