Can a Hp pavilion all in one touch smart amd a6 quadcore handle gmod and minecraft at medium settings?

If it doesn't overheat and/or end up with a dead screen first, sure. Minecraft isn't a very intensive game. What you really need to worry about is your graphics memory, you should be fine as long as its 64MB or more and it shouldn't matter if its VRAM, dedicated, or integrated.

Seriously though, if what you're doing is considering the purchase of a new HP, don't. I haven't had an HP laptop last more than 6 months before it starts getting hot and kills its screen, ever. I recommend Asus or Lenovo.