Well, since now you told us you want to write some web applications with perl, you need a web server. You can use Ms Internet Information Server which is included with Win2k. But likely your ISP will use Apache, so it's easier to use it as well. See httpd.apache.org and choose the major version your provider is using (1.3.x or 2.x). If you just want to write Perl/CGI scripts, the version doesn't really matter

You can download mysql from Mysql and chose the same or a newer version than your ISP (the major versions are 3.x, 4.0.x, 4.1.x) and install it

if you want to develop with mod_perl or GD, see theoryx5.ua.winnipeg.ca/ppms for additional perl modules not available by activestate...

if you want apache2, you can alternatively go to apachefriends and download XAMPP for windows which contains Apache, MySQL, PHP + PEAR, Perl, mod_php, mod_perl, mod_ssl, OpenSSL, phpMyAdmin, Webalizer, Mercury Mail Transport System for Win32 and NetWare Systems v3.32, JpGraph, FileZilla FTP Server, mcrypt, eAccelerator, SQLite, WEB-DAV + mod_auth_mysql