mddolloff, it comes down to how much time you can spend on it and your own skill level. If you want quick and easy, $10 SOHO routers are quick and easy. A PC firewall will always be a bit of the labor of love, but they pay off in extra power and extra learning.
If you're not a UNIX person, Smoothwall, IP Cop, or some other firewall-oriented Linux distribution with a web-GUI interface. These are basically SOHO router on steriods solutions.
If you are a UNIX person, run OpenBSD. pf good.