Simultaneous runway operations were in progress at Sydney when VH-MJH was cleared to land on runway 34, with a requirement to hold short of runway 07. After the aircraft had landed the aerodrome controller (ADC) instructed the pilot to take the first available taxiway to the right. This was taxiway 'Hotel', located about 238m from the runway 07 simops lights. VH-RMN, a Boeing 727 which was lined up on runway 07 was then cleared for takeoff. VH-MJH was then observed to have passed the taxiway and was told to hold short of runway 07. The aircraft continued rolling and when the ADC became uncertain that the aircraft was going to stop before runway 07, he instructed the aircraft to stop. The aircraft did not stop and the ADC then cancelled the takeoff clearance for VH-RMN which was now rolling for takeoff. Another aircraft, was sent around from a 2 mile final approach for runway 07. VH-MJH came to a stop mid way between the stop lights (holding point) and the edge of runway 07. After VH-RMN had stopped VH-MJH was cleared to cross runway 07 and vacated runway 34 on taxyway Bravo 6. The first officer was the pilot flying VH-MJH until after the aircraft had touched down. The captain then took the controls during the landing roll, and the first officer turned his attention to the after landing checks. The captain stated that he had not heard the transmissions to stop. It was not until he noticed that the first officer was transmitting that he realised that he was not monitoring the tower frequency. After he had received a landing clearance he had intended to deselect the company frequency and had inadvertently deselected the tower frequency. The first officer had subsequently acknowledged the transmissions from the tower, and was not aware that the captain was not monitoring the tower transmissions. The first officer realised that the captain was not following the towers instructions when the aircraft passed the taxiway and he instructed the captain to stop using both verbal and visual signals. By this time the aircraft was nearing the runway intersection. The captain misidentified the position of taxiway Hotel due to the position of a large mound of earth which had previously been located south of runway 07, but which was now located north of runway 07. This gave him a false impression as to the location of the taxiway, and was not aware that he was approaching the runway until after it was too late to stop before the holding point lights. Significant factors 1. The captain inadvertantly deselected the tower frequency just prior to taking control from the first officer. 2. After handing control of the aircraft to the captain, the first officer diverted his attention to the after landing checks. 3. There was a breakdown in crew co-ordination procedures.