Isn't the acer aspire one a NETbook? Meaning it has a very slow CPU in addition to a slow video card. You will be stuck with playing games about 5 years old or more. I think the old D&D games may run OK on your laptop.
This is a good catch (that I missed), the Acer Aspire One is indeed a netbook. The AMD based Acers will probably out-perform the Atom based Acers in the Aspire One family. This is true primarily because the AMP GPU will run circles around the Intel integrated GPUs.
The small screen size is going to be a pain, no matter whether using an AMD or an Intel solution. Regardless, you might be able to run Torchlight on either, but performance is going to be poor with most modern RPGs.
Just not enough horsepower. Besides, netbooks are not built for gaming. Get a full-size notebook if you are gaming.