Could you open a File - Save As dialog (as in paint or notepad) and tell what the sort order there is.
The sendto is sorted alphabetically by default. Some people report their's are sorted by date. This is similar to a problem with File Open/Save As dialogs. So would like to see if both of yours are sorting by something other than name.
Also confirm the order on the menu with the actual files (type sendto in Start Run) and see if it is sorting on date or another field.