G4 800 or Mini, RAM, and other contingencies, i really need the help so sorry :) Options

[pinnocio]

hello mates, i'm so very new to mac.
i want to leave PC (hopefully for good) and move into mac.
now i don't have much money and i'm concidering 2 machines -
used Power G4 800mhz with 512mb
or the Mac mini 1.42mhz with 256mb
now here the story doesn't end...
i plan on buying (for both so it doesn't matter regarding the money cost)
a FIREWIRE HDD 160GB 7200, M-AUDIO FIREWIRE AUDIOPHILE and a 1GB Ram stick (not apples so again, it doesn't regard the money cost).
I use my current P4 2.4 with 1GB ram and EMU 1212m mainly for MIDI projects, classical and film scoring using only samples through kontakt (nothing external) and VST plugins (some VSTis but nothing heavy).
My dilema is very simple i guess but for me it's a mess, getting the Power G4 means i can have up to 2GB RAM but a slower Processor and an older version. Getting the Mac Mini means i'll have a brandnew hardware but only a 1GB limit.
As i said i plan on loading alot of samples but as i've calculated the amout that i load into kontakt, it turns out to 750-800 MB, so a 1GB plus Virtual memory can handle it... i guess.. but still i havn't god a clue if it's worth it... any suggestions? thanks alot, Yoav