PAL to NTSC or vice versa?

[Macglobal]

>> Can you please help me with advice - I am using VLC on my iBook (OS-X)
>> to show video CDs, which I want to present to groups of people on a TV
>> screen. It seems that my TV does not have multisystem, nor the option
>> to change the system manually. Is it possible to change the system in
>> the output from my computer - e.g. from PAL to NTSC or vice versa? And
>> if so (which I hope), how do I change the setting?