RCT3- Specs with Vista- Problems

Here are my CPUs specs:

Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz

Graphics: NVIDIA GeForce 8300 GS

Gaming Graphics: 1406 MB Total available gaming memory

System
_______
-32 bit operating system
-Dell

Storage
_______
-224 GB free of 298 on disk partition (C:)

DirectX10 DirectX version

RCT3 keeps freezing up in different spots while playing the game, sometimes on the menu and sometimes in the different gaming modes. I need help...now!