Sims 2 will likely run. Not sure about Sims 3. That all-one-pc will be relying on the Intel HD 2500 which is not very powerful. Since Sims 2 is an older game with lower requirements, I don't think I will be an issue. If you buy an all-in-one with an Intel HD 4000 graphics core, then I think you should be fine with the Sims 3.
You should also see if Sims 2 is compatible With Windows 8.
Based on the video below, the Sims 3 seems to be running on an Intel HD core; no model #. However, it is only at 1024x768 resolution. Skip to about 4:25 into the video because the person did not even bother to edit out the load time. The Sandy Bridge Intel HD 2500 is more powerful than the 1st generation Core i3's Intel HD graphics core. However, in the entire scheme of things it is still a very weak graphics core. I suggest you read through the comments for more info.
There is another solution some offered, but it involves having a working version of Sims 2 installed because you will need to copy some files. Additionally, this solution only works for with the University Life Collection, and Open for Business Collection expansions.