To answer your loading problem:
Originally Posted by Juliancahillane
Oh I just realised your going on about crysis 2 not loading lol........thats a well known bug and nothing to do with your hardware. You must load the game by selecting replay mission, it wont load from saves within the mission. I thought your problem was with your hardware by the way you were talking. And yes a quad core will help crysis 2 because modern games generally use more threads
To answer your poor performance, its your e8400 and DDR2. I've seen GTX460 1GB cards maxing out Crysis 2 at 1080p (with moderate AA levels). So its not your GPU. Crysis 2, DiRT2, DiRT3, BFBC2, all of these games want a quad core to run optimally, and a high clocked one at that.
The problem, is that you're trying to run top end graphically games from today, on hardware that came out in 2007. It's like trying to run Crysis 1 on a Pentium 3, and complaining about poor performance (I've seen that before by the way). Not trolling you or anything, just stating facts.
And no, I'm not saying that you have to be rich and keep up with the current generation of hardware all the time either. There's nothing at all "wrong" with your machine at all. But that's exactly the reason why you're getting lower performance than expected in this graphically intensive games. You'll either have to upgrade, or live with lesser graphical settings.