May I suggest a CPU / Mobo combo?
Soltek SL-75FRN2 Motherboard (Nvidia NForce2 Chipset, DualDDR400, 6 USB2 ports) also known as the Golden Flame.
In recent reviews the fastest and most configurable mobo around. Currently retails at around the £60 mark
AMD Athlon XP 2400+ Retailing around £50
DDR 400 Ram, whatever amount you want up to 3Gb BUT I would advise you to get 2 sticks rather than just one, fit them in the 2 YELLOW DDR slots on the Golden flame and it enables dual channel mode. (Works faster)
not expensive, but an excellent combo
even LOOKS good in a case with a transparent side panel.
Installation is painless, although the chipset is too new even for XP to support, but the drivers supplied with it are easy to install.
an online comparison of the 2 (Asrock Vs Soltek) is here
http://www.digital-daily.com/motherb...ock-vs-soltek/