Just so you are aware of the game mechanics regarding saves...
There is only 1 Quicksave slot. Each time you Quicksave (F5), it overwrites the previous Quicksave.
You can make as many Manual Saves as you want (esc to menu, click "SAVE"), up to the limit of your Hard Drive storage, although I'm sure there must be a game limit. If there is - it is very high. If you have a lot of saves in your \gamesaves folder, it WILL slow down access for saving and loading, so you should copy out old saves frequently for best performance.
The game will not allow you to save while in "Action Mode", during cutscenes, or during scripted events. Many times this action mode will persist for many seconds after a battle with a foe - and will manifest itself by seeing the "Cannot Save at this time" dialogue on the left of the screen. You will have to wait until the action stops and Geralt drops out of action mode before you can save again. You will notice the same kind of delay after killing a monster, and having to wait a few seconds before you can access/pick up it's loot.
If you simply cannot save at all at any time - then ensure you are playing under Administrator, or have Admin rights, or are in the right Profile (if you have multiple ones on your PC).
If nothing works, then back up your saves, uninstall (including deleting leftover game folders) - reinstall, patch to 1.1, and the 1.2 patch will automatically install.
For installation difficulties, check the official FAQ on it... http://www.en.thewitcher.com/support