Does the Kies software allow one to type and send text messages from the PC?
But, on the other hand, you can use the Kies Air application, which you can obtain through Samsung Apps. It allows you to access your mobile on the desktop browser if both PC and phone share the same Wifi network.
Then you would be able to send/recv messages on the desktop, amid many other things like accessing photos, videos, contacts, call logs, music, file system... and so on. It is like a small web interface to your mobile.