For a web server on windows xp you can use IIS which is a proprietary Windows package. You can also opt for Apache which is an excellent open source web server. For email you can't MS Exchange 2003 because it's not supported on XP so you have to go with another open source email server, I recommend hMail. And just googling chat server will give you a plethora of options for chat server software. What I would recommend is that you switch over to Linux and have everything open source as opposed to having to run all these servers on an XP machine unless you want to upgrade hardware and software to a Microsoft server operating system.