All the documents on my desktop are no longer associated with the program they were saved to. They are now opening as notepad documents with coding. They are all labeled with the same long letter number combination.
Could you provide some more information on what happened? It would be of help.
I believe you can start with just restoring your system to an earlier restore point. Check this tutorial out (somewhere in the middle): http/www.howtogeek.com/howto/windows-vista/using-windows-vista-system-restore/