A Sandy Bridge i3, i5, or i7 will run those games just fine. The integrated graphics in the Sandy Bridge chips can run The Sims 3 on medium at a bit above 30 FPS, according to
http://www.notebookcheck.net/Intel-H...0.37948.0.html, and it shouldn't have an issue with Zoo Tycoon. But AMD graphics would be my reccomendation, like the 6650M on
this notebook. That is
way more powerful than Intel's integrated, and rather cheap. (That laptop, with a quad-core, will run you $600)