FFX is one of the better games on PCSX2, it was it's "flagship" title so to speak. Looking at his specs it would run very well, however his ATI card might throw a spanner in the works. PCSX2/gsdx prefers nvidia, fact.
FFXII runs fine too, although there is slowdown, even on my OC QX9650...DX10 rendering for the GPU plugin is almost required though, as the DX9 rendering mode needs serious help... PCSX2 almost requires a Quad to run most of the games well...I also know GPU power does not count much; I ran my 9800GX2 on one GPU for a week, with no FPS change. PCSX2 LOVES CPU power (which makes sense, as most of the code is for syncing up the 2 PS2 CPU's and Register communication). PCSX2 .0.9.6 was a huge release, as it runs a ton faster and a lot of rendering bugs (at least in DX10 rendering) have been addressed. I'd say 25% of all PS2 games are playable speeds without noticable glitches, 50% playable in various forms (speed or graphical issues), and less then 25% not playable at all. EDIT Once i beat FFXII, every FF game except 11, which does NOT count, will have been beaten by me (counting Adventure, Legends, Tactics Series, Crystal Chronicles, Mystic Quest, ect). Just in time for a new release
PCSX2 doesn't use more than 2 cores and likely never will. The reason you're seeing an improvement with quad core is because you're using an ATI card. A lot of the rendering is offloaded to the CPU which is where your extra two cores come in. A 9800GTX and fast dual core (3.4Ghz +) is more than enough for PCSX2 and most games.
Man I was running that with what I got and a 8800GTS when my rig was stock and I was getting 60 FPS. Its really the improvements with the emulator recently that speeded things up so fast.
the very last boss only exist to complete the story, he is not really a boss that you have work hard to beat.
sorry cant ruin it, depends on what you perceive as the last boss, but yep you can die at any boss, unless youre uber leveled up