Upgrade time
Well, I went and ordered my new PC bits from Komplett.ie. I look forward to their arrival and cutting my hands on sharp edges of my PC case when I go to put everything together!
In the end, I went for the following parts:
Sapphire Radeon X800 PCI-Express x16, 256 bit memory interface, 256MB GDDR3 memory
AMD Athlon 64 3200+ Socket 939, 512KB cache
Abit AN8 (non-SLi) Socket 939 motherboard, with PCI-Express, gigabit Ethernet, integrated sound, firewire, USB2.0, etc.
Of the stuff for sale, only the Gameboy Advance SP and Motherboard + CPU are left, and I have offers for the motherboard + CPU 
