This is one oxymoron I haven't heard before. So, it runs when it's NOT frozen... but it keeps freezing... so how can it run?
Anyway it would have been much simpler had you told us what kind of notebook / laptop you're using. From what I can see, that CPU (T2330) is exclusively used in underpowered notebooks that are good enough for checking your e-mail and writing your assignments but not much else.
Typically, this type of notebook does not have a graphics card but an integrated chip so you don't have to bother trying to update your GFX drivers. Your CPU and RAM will be pretty much exhausted by just pushing Vista over the hill.
I am almost certain that you don't have enough grunt to run FS2004 satisfactorily. You can try to go through your settings within the Sim and push all your sliders to the left, and disable all unnecessary settings.
If your computer still freezes after you have changed the settings to the minimums, I'm afraid I haven't got a clue what might be causing it.
I should also point out to close any other applications while trying to run the Sim.