I've used Ubuntu 5.04 before on my laptop, which has a VIA C3 CPU, meaning that i had compatibility issues with Fedora, so i'd say you can rely on it for almost any machine.
Programs are easy to install on it too, so it's quite a good distro for beginners, but Linspire was better imo, however, that costs a hell of a lot of money, so i wouldn't go for that.
Windows XP Pro 17" LCD Monitor (1280 x 1024)
nForce3 250 Chipset Athlon 64 2800+ w/ C'n'Q
1 x 512MB DDR400 CL3 SDRAM 40GB IDE 7,200rpm HDD (8MB Cache)
nVidia GeForce MX420 64MB PCI On-Board Audio