Just a newbie seeking help!

[l3lake]

Hello everyone 1st of all i have no idea if im posting this in right section if im not plz do forgive me
Anyways i have a problem using my emulator,my problem is when i am in main menu of the game i get clean 60-65 fps games works perfectly video,sound are perfect.
But when i go little further in game (Example in gran turismo 4 when i start to look to buy cars and to pick licence to play or actually play the game)i get huugee fps drop it goes down to 20-30 sound and audio are horrible and the game from that point is pretty much unplayable.
I do hope you understand my problem,i might have explained it weirdly lol.
Anyhow i am a complete beginner i have tried some stuff explored a little with some guy who helped me with the settings and i managed to get few fps up but still unplayable.
And 1 more thing,when i had to pick plugins for the GS settings i pretty much had no idea for what settings my processor is compatible i totally randomly picked,maybe i messed up there?
My pc specs:
processor: AMD A-6 3500 APU with radeon™HD graphics 3 core 2.1GHz
RAM: 4 gb ram but i have 1gb locked so i am using 3gb atm
32-bit system
Sry for the long post

[refraction]

Your CPU is pretty slow. Aside from overclocking, the only thing you can do is check the following 2 options.

1. Check you have MTVU enabled under Emulator Settings -> Speedhacks.
2. In the GSDX config make sure the "Native" box is ticked.

[l3lake]

Didn't help that much but i did saw some better gameplay but still laggs lot's,thanks for the help !!
I rly thought 3 core would be enough to run the emulator,pity i wanted to get back on the good ps2 games :\
Well just out of curiosity what kind of specs do i need to run pcsx perfectly ?

[refraction]

3 cores is enough, 2.1Ghz however is not, you need over 3Ghz with 3.4-3.6Ghz recommended, your cpu is nearly half that.