Help purchasing a new video card please?

whats the best video card to get to enable me to play far cry 2 dead space etc.? i have an intel pentium dual core processor, 4gb ram and a mobile intel 4 series express chipset family. but the pc still wont run the games at a decent rate. they are very juddery, is it my graphics or my processor? if it is my graphics whats the best new card i should buy for the cheapest please? its a laptop by the way. thanks|||It's the graphics device. It is most likely integrated in the motherboard and can't be changed