That's a fairly broad question, so there really isn't a yes or no answer. Firstly, frame rate generally flucuates so even if you can achieve 40 frames you might average at 31-35 depending on what is going on in game. Also i personally think of 25 frames a second as not so good, as once it goes below 30, that is where games practicly turn into a slideshow and the game becomes unplayable.
Also you watched a side by side comparion with what?, was the system you watched on youtube the same as yours or a different system?
I'm not sure how demanding The Witcher 2 is, though your laptop should probably handle it decently in areas where not a whole lot of activity is going on, as it's pretty beefy for a laptop.