I don't do "fancy" PC - mine lives beneath the desk and allows me to surf the web, fuck around with video's/DVD's, and stream my music to my hifi - so it don't need to be fancy....
The PC is a Dell Optiplex GX260;

It's a clam-shell design, so it opens, err, like a clam

without messing around with screws
Inside is a 2.8ghz P4 chip (no idea what socket or any of that) and 1.5gb (three 512mb sticks) of RAM. a primary 60gb HDD for running the OS, programmes and saving data "procured" from the web

to - which i then moved to a 320gb internal slave drive. The important bits from this are saved to an 8gb external HDD
NEC DVD-RW drive, and a stock Dell DVD-ROM drive, stock floppy...
Stock on-board graphics (I don't do gaming) but I upped the audio to a Trust twin PCI (single PCI card with a "daughter board" PCI slot header) optical digital 5.1 card. Main PCI card header has the 5.1 analogue outputs, and the daughter board has a pair of optical (in+out) and a pair of digital coaxial (in+out) connections. I use the optical to stream music ot my hifi, which is only 2ch stereo, but it will stream Dolby Digital and DTS multichannel audio to a reciever than can decode
Bluetooth USB dongle for file transfer to and from my phone and my downstairs PC.....
Stock Dell 17" TFT monitor, stock Dell keyboard, stock Dell wheel button mouse, oh and a USB card reader for my camera's
Nothing fancy, but does pretty much all that I want it to