I don't have much to add at the moment (although I wrote a lot after editing, it's just elaborating on the same thing) and I was too exhausted yesterday afternoon to check in..
My remark on PS2 emulation is that they are improving PCSX2's multi-core capabilities and game compatibility CONSTANTLY, so if PS2 emulation isn't the centerpoint of your computing/gaming on a low end machine, go with the AMD. Its possible that within a few months, contributors to the project will find a way to make the primary PS2 emulation plugin work better with AMD, or work better altogether. The main reason that low end AMD's suck so bad, at least in my knowledge regarding this particular emulator, is that they are not known to work with the better versions of this plugin, and Core series Intels can use all types (SSE 4.1 being the ideal, as it includes the most recent instruction sets).
I have one of the best AMD CPUs from 2011 in my desktop, which is a 6-core, but it only works using the basic version of that main plugin (SSE2). But also note, my ASUS AMD-Turion 64 x2 2.0GHz laptop from fall of 2007 was able to run KH & FFX at playable/realtime speed using that same plugin after some tweaking (I think frameskip was a big factor) at the lowest resolution. In fact, at least one of the screenshots on that guide toward the end (showing the opening sequence of FFX) were taken with that computer.
It sometimes looked crap on my laptop screen compared to the way the games looked on a tube TV with composite RCA video cables (video + l/r stereo audio). It takes so much horsepower to increase resolution and graphical effects to compensate for high pixel pitch on digital displays.
I think ,ultimately, that your performance on AMD with this emulator will depend on how much time you're willing to research games you have trouble with on the PCSX2 forums, and how much time you are willing to spend tweaking the emulator's settings.
The difference in emulation on PS2 may be quite noticeable at present, but there's plenty of other things the AMD A-series will do better than the i3 w/HD3000 graphics (which, although I did say was okay, just as Originality said, it's only okay for emulation; and for all other gaming purposes in the past couple generations of PC games, it's sub-par).
At the time of my post here, Best Buy's website is down and I can't look at any of the links. If I have time, I will return later to verify their recommendations.