Thats it. Just turn AA and AF on. Like you said your really not noticing much due to your poor card. Also, you wont notice it either unless all settings are turned up on the game options.
AF basically makes things less blurry at a distance.
AF at 2x would make anything infront of you at say, 20 feet, game wise, blurry, 4x would make it so you see less blur, and once you get all the way up to 16x, you won't notice any blurring in the distance..
that's the best way I can describe it, maybe someone else can describe it better? :cheers: