I was setting up the forums for the Pioneer, which are pretty much done, and I noticed that the forums were acting really sluggishly. It's a phpbb3 forum. I've used them before and they've seemed pretty snappy to me, so I figured our webserver, which recently got moved to a server with less resources (but more hard drive space), was just acting slowly. But I began to wonder if that was really the case. My own pages, written in ASP.net were preforming just fine. So I researched it and apparently there's something called FastCGI that doesn't come pre-installed on 2003, but it greatly increases the response of script interpreters like PHP.
So, I downloaded the FastCGI extension from Microsoft, installed it, then added this hander for PHP files on the website of interest:
C:WINDOWSsystem32inetsrvfcgiext.dll
After that I re-ran the PHP installer and told it to use FastCGI. It worked perfectly. Now my phpbb3 is performing much faster, even though the web server still isn't as powerful as it should be. It works; that's all that matters.