yes it's the same, but only allow required port in your firewall for incoming connections, see there:
Managing a public server requires some skills to avoid bad things, so be careful (there are many bot computers and malicious users that will connect your server and try things like php attacks, don't leave a port open to a misconfigured server or to something you don't want like the telnet interface of rappelz servers)
And I doubt you have something older than a windows server, if you really have windows 98, it's a desktop OS and have probably many known security issues. You can see the OS version by opening computer's properties (or via shortcut: Win + Pause)