Dual Core vs Quad Core?

[gemini_9]

Well I just downloaded Dolphin and have been playing around with it a little. The reason I downloaded it is that my ex and I broke up. Unfortunately, most of the gamecube games were left at her place. Bummer! I didn't really want to go out and buy another gamecube and another copy of the games, so I turned to the emulation. So first off, thank you dolphin for saving my favorite gamecube games!

The first game I am trying to play, is Paper Mario. I've noticed that it runs much slower on the computer than it did in the actual game cube console. In reading the FAQ, I think this is normal, but I wanted to see if there was a way I could speed it up at least a little bit. I average 24-29 fps, but it's pretty sluggish as compared to the console.

I have a dual core AMD processor. Athlon II 64 bit 6000+ 3.0 ghz (windsor) to be more specific. I've considered upgrading to a quad core, but I've heard it impairs emulators. For example, I've heard that snes9x and virtuaboy (gameboy advance) only uses one core. So if I'm using a 3.0 ghz dual core, I'm actually only getting 1.5 ghz from one of the cores. Is this true? I've heard some pretty bad rumors about Quad Core processors and many say it may not be a worthwhile upgrade. What say you?

Here are the rest of my specs:
AMD Athlon II 64 6000+ 3.0 ghz
4gb DDR2 800mhz (OCZ SLI-Ready Edition OCZ2N800SR4GK)
Biostar TF8200 mobo
EVGA GTX 260
2x80 gb SATA II RAID Striped
XP Pro, Vista x64, Win 7 Multiboot

System isn't overclocked. Everytime I try, I get the blue screen in Vista. Who knows.