What's a good configuration for a web development server for local network?

We're about to purchase a development server for our team of web developers - php and javascript programmers. We're planning on running LAMP and Subversion. What is the best hardware (processor, memory, manufacturer) and software (flavor of linux, setup, etc.) configuration? And what's the best way to network it to a team of 4 Windows machines?

It really depends on your budget. "Best" hardware is, to my mind, the fastest and largest capacity you can reasonably afford. For this sort of server, I'd choose more RAM over faster processor, and fastest/biggest hard drives I could find. I'm partial to Slackware Linux, as it's free and very stable. If you're using Subversion, then just regular old TCP/IP should be sufficient, but you could easily configure Samba for Windows sharing if you chose to. The level of your question indicates you're not particularly comfortable doing this yourself, so it's probably worth your money to pay a consultant to help you make these decisions and get it all installed and running. That gives you the additional safety net of having someone available to help you out if things go sideways.

I'd use (I do use) PCLinuxOSBE for the server. You get everything (and more) installed as soon as you boot - AMP, POP3 and SMTP if you need them, Webmin ... (I can't remember if phpMyAdmin is included, but it's a simple download.)

I put my servers on the network and map a drive to the htdocs directory on my Windows machines, so it's trivial to do development work. (phpMyAdmin for remote MySQL administration, although we run that on a separate box because we need the bandwidth.)

Hire a net admin. I can do it over the phone.