As you have found, while Perl is supported on various Microsoft environments, there are several nits that wear thin after a while. I would recommend you have two environments - your existing Win 2k and a Unix-like environment. Just as with web developement, you (should) test your designs on as many different browsers as possible, having a Unix and a Windows environment to test your Perl scripts is a good one.

In my experience, there is no substantial difference - from a Perl development point of view - between any of the current versions of Unix - the commercial ones (Solaris, HP-UX, AIX); the BSD versions or the Linux versions. Since your main aim is to have a good "unixish" Perl development environment, it is hard to go past a recent Red Hat distribution. They are easy to install, easy to upgrade software using their RPM packaging, and have extensive documentation. Other people may prefer a more "traditional" Unix version, like the Linux Slackware, or one of the BSD versions; but for your need, Red Hat shoudl be more than adequate.

You don't need fancy hardware - I have a 4 year old AMD K6-2 300 MHz machine, with 64 MB of memory, and an 8GB disk, which runs just fine. As well, with this environment, you can start to expand your skills. Since you can now run your own web server (Apache is included), you can learn all about how the web server actually operates. Install mod_perl, maybe some tools like Template::Toolkit, HTML::Mason, or EmbPerl. Connect your windows machine to the Linux machine, get some understanding of TCP/IP networking (say, DHCP, DNS, firewalls, ip masquerading).

Plus, you shouldn't have to pay al lthat much for a good manual and the software - even check out your local library.