I have that same laptop and it works just fine. The only lag I experience is when the scenes are too complicated and huge and especially when using things like GIProbes in 3D (this is logical since these are cpu intensive). In 2D I've not come across any of the problems you have mentioned. I have 5GB of ram though which may be the only difference we have so the problem is not the hardware.
Have you updated the graphics driver? Most of the times that's usually the problem.
Also check whether you are utilizing the full cpu power. Click on the battery icon (bottom right of the screen at the task bar) and move the slider to best performance.