From your description, you are hitting the limitations of your system, not Carrara. Your scene render settings are using everything Carrara has. The one thing Carrara needs for a scene like that is tons of memory - 2G is not enough. 

Unlike programs like Photoshop, Carrara doesn't spool off rendering memory requirements to disk drives. Carrara can spool textures but that is different than the actual render calculations. 

By the way, you can crash out any 3D application by not having enough memory - C4D, Vue etc. Trust me on that. ;-)

Mark