I bought my family and mini and they are sending me there g5

MY first mac since the mac classic
they are not experts so i want someone here to help me with this exchange...
They have a G5 with bluetooth keyboard and mouse...
I got a loaded mini with internal bluetooth...
I also purchased a wired keyboard and firewire cable.
I guess my issue is with the setup and file transfer.
i am going to have them unplug all from the g5 and plug into the mini
then I will plug the wired keyboard into the mini for setup
and then connect the firewire cable between the two and turn on the g5 holding T on the bluetooth keyboard.
so far correct?
then follow instructions on setup
1. first possible problem...is the bluetooth mouse going to pair with the mini for setup?
if it does and I follow instructions will it ask me if I want to transfer from my G5 files and software?
2. should I turn on the g5 in firewire mode during setup or before?
and then when i am finished two things...
1. how do I pair the g5 keyboard and mouse to the mini now....will it do it automatically if the g5 is powered off.
2. when I boot the mini at this point will it just be a mirror of the g5 hard drive at this point?
anything i am missing?
is this going to be a disaster on my families end?
Thanks for any help or advice...
looking forward to switiching...