yogsloth: What am I doing wrong here? Because so far, this is just unplayable.
First, the choppy cutscene problem is mentioned in the sticky thread too. Try toggling your "depth of field" setting in the graphics options. If it's off, turn it on, if it's on, turn it off. This should help. The setting only affects cutscenes.
As for your first post, as you've probably learned already, clicking rapidly doesn't work. You have to click ONCE, then wait until the correct time to click again. As for the over the shoulder camera jumping around, I didn't have as much of a problem with this. Maybe try changing your mouse sensitivity in the game? Lowering it might make the camera more steady. Also, the cursor doesn't disappear when it's not on an enemy, it just becomes a very small single dot. It can be hard to see, however.
I think lower mouse sensitivity will help, and just trying to keep the mouse steady while fighting. Don't try to look around while Geralt is attacking or you'll lose track of the enemy you're fighting. With a little practice you'll get the hang of it.
Finally, the start of the game isn't that great, but it really picks up in Chapter 2. Try to get that far if you can. Having said that, if you really aren't liking it, don't force yourself; it's not for everyone.