Is it possible to use the Infrared capability of the GBC for a IR remote control ?

Yes.The GBC IR transmitter can even operate at over 100kHz. But, transmit distance drops off dramatically at 100kHz and higher.

One person was able to code an IR remote that would transmit to a TV reliably up to 3 metres (10 feet) and unreliably up to 5 metres (15 feet).