One word... No, followed by more words... Jet Force Gemeni does not crash due to your enormous CPU speed. Are you sure you are using the latest drivers for your motherboard and graphic card? If not, try to update them aswell as your DirectX drivers.
No, both versions are compatible, I am not sure about non US versions though. But in Jet Force Gemini (US) [!] you are unable to shoot, which makes it unplayable. And no jarret, atleast it does not happen to me, have you tried both graphic plugins supplied with Project 64 1.40, Jabo's D3D 6 and Jabo's D3D 7. I did not succed in making it crash, at any point in the game. Are you using the default core and plugin settings?
Go to Start>Run type dxdiag and press enter
Go to where it says Display and see what name it says, that is your graphics card. If it says {Something} GeForce then you're fine.
hmm.. when reading your other post it seems that you have the same problem with more(all?) games , maybe you do have a s3 chip based video card like Slougi suggested.
Does the Kiosk version run fine ? Does it have a good frame rate and shoot? The (u)[!] version runs ata super slow rate, and of course, it doesnt fire.