I hope you don't expect to do any serious photo processing with it!

I am with David on this one. Image processing does not put much strain on video processing like games or 3-D does, so you can go for a relatively low end card. The monitor is critical - if you can not calibrate it accurately, accurate colour is impossible. When I set up my graphics workstation, I chose two high end 19" Samsung CRT monitors. The main screen was accurate out of the box, and worked a couple of years before needing calibration. Now, I would probably go for a pair of high-end flat-panel screens. I use a Colorvision Spyder2Pro for calibration.
Two of my workstations.

A fast processor helps, but the most important thing is to have sufficient RAM - as in two gigabytes. Less RAM and the system will have to page to the hard-drive and relatively speaking, processing will become glacially slow.

Larry,

I would agree that the 3D or gaming accelerators that drive up high performance video card prices are not necessary, but 2D graphics processing ( a good quality codec processor) and a full-fledged LUT library are essential. For Windows machines the two best brand choices are ATI and Matrox Millennium for good Photoshop support. For both a good buy at a fair price and a good selection try TigerDirect.com/.

Again, in total agreement.