Hello all!

I'm thinking of doing a project of making a web-based interface for router configuration based on Linux, running common services like iptables, squid, dhcpd, and named. Routing table and the configuration of those value-added services are done from the web interface (just like the ones that dedicated/blackbox routers have). I'm planning on using PHP's shell interaction commands like system(), exec(), etc. to run the commands and scripts, and its file manipulation functions to modify the config files. I need some advices:

1. What distro should I use? Why?
2. What are the major obstacles in making this project a reality? Are there workarounds to solve them?

Help is much appreciated. Thanks in advance.