CalinRO: I have the Witcher 2 retail copy, i installed the game, and the launcher patched my game in 1.3 version. And i also have the latest nvidia driver, the 280.19
And if i start the game, i get full screen but with the windows 7 taskbar below. WTF !!
Check the full screen setting in the launcher's options.
If it's enabled, you could also try hitting ALT+Enter while TW2 is the active task to switch to full screen mode.