Generally speaking to get the largest amount of games you need a CPU at around 3.6 ghz (over clocked is the best way to get there economically, 4.0 is ideal) Your CPU will still play a large amount of games, especially ps2 emulators, wii games tend to be more demanding but it varies game by game.
For emulators, the part that has the effect of antialiasing is the internal resolution. At 1080p 3x plus is desirable. But obviously anything over 1x will look better. This is mostly affected by the gpu. Your gpu is a bit weak but should play the games well enough. Better gpus will give u better results. Next gen games will run sluggish for sure.
What is your budget? And do u only want to run emulators and play most games on console? If u have the exact components and prices I can help tweak ur build without increasing costs that much (I believe)







