Arduino to start a music file and a jitter sequenc

I didn't know whether to put this in the hardware or software interfacing forum, since it involves both.

Hi there I am a complete newbie at this.

I was just wondering if it was possible that if I connected a Infra Red PIR Motion Sensor which is at coolcomponents (I can't link because of low post count) to the arduino would ir be able to do start a BlinkM light sequence, a music file, and a jitter patch all at the exact same time?

If so how would I go about doing this?

To which sockets do I connect the sensor to, and what kind of programming to I need to operate it?

Would it be best to bring the music file into a max msp buffer and get it to trigger it that way some how? How does the arduino interface with max msp? Also since the BlinkMs are i2c networked.. how do I get the Arudino to tell them to start and stop etc?

Many many thanks!!

Mark.