Open up kies and make sure it is up to date. Leave your phone unplugged. Then go to "troubleshoot connection error" on the homepage. Run it. Let it update your device drivers. Once it succeeds, kies will have the drivers it needs. If your phone still doesn't update, I would have to assume the problem lies elsewhere.
PS- if that was what you were doing and you get the error message, uninstall and reinstall kies and the drivers, they should be listed in add and remove programs.
PSS- you don't need to install both the driver package and kies from samsung both. Kies will install it's own drivers.