Yes I did download the demo. It runs too slow.
So I have no other options?
If we weren't dealing with a laptop, I'd say a faster video card. But that's nearly impossible with a laptop. The slow framerate you experience with the game is due to the graphics system not being able to keep up. The increase from 2GB to 4GB (even if you could) would not make much difference, if any. And, it wouldn't be cost effective to buy a new laptop with gaming capabilities just for that game. But you may want to add a gaming-capable, upgradable desktop computer
to your collection of electronic toys.