Help AppleiMac G5 20August2004 new to mac

[japple28]

Hi I have just bought my son a G5 from ebay all works great apart from the stuff he wants it for, he want facetime so he can call me at work and see me, but cant use facetime with tiger is there any way I can upgrade to SL?
Mac spec

MPN: AppleiMac G520August2004 Release Year: 2004
Processor Speed: 2.2 GHz Release Month: August
Memory: 2 GB Product Family: iMac G5
Hard Drive Capacity: 500 GB Screen Size: 20"
Processor Configuration: Dual Processor Type: PowerPC G5
Operating System: Mac OS 10.4, Tiger

Description
This is a customized product of Apple Desktop iMac G5 20" (August, 2004)

Product Identifiers
Brand Apple
Product Family iMac G5
Model ID PowerMac8,1
Model Number A1076
MPN AppleiMac G520August2004

Processor
Processor Type PowerPC G5

Display
Screen Size 20"

Miscellaneous
Release Date August, 2004

I hope that helps as Iv never used a Mac before, and I hope som1 can help me, Thanks all.

[bizzle]

You can't use Facetime on that. You may be able to find an older version of Skype that works on PPC, but I think they may disable older versions past a certain point.

Edit: here you go, http://mac.oldapps.com/skype.php?old_skype=37#Download

[Nameci]

You can only have facetime if you are running snow leopard. Since it is an iMac G5 it would not run snow leopard, and the latest OS that can run is leopard. Try skype.

Snow leopard can only run on apple machines with intel processors, iMac G5 has a PowerPC processor.