Upgrade NT/W2k file servers to Linux, Use Linux as Servers for Windows Clients

The Questions:

So how do you do this?
Who is it for?
What does it cost?
Is it safe to do?
How long time does it take?
How much more load does this handle than a W-NT/W2k server?
How much do you save?
What do you need? Do you need all the software and service on all servers? and
What do you get?

The Answers:

Upgrade your servers to an Open Source software system.
Use Linux, Samba and Webmin as a base for a new server system.
Systems with a smaller amount of servers can do this upgrade in a couple of days. Larger server fleets can absolutely do this as well but should probably choose different admin tools
The software is free so this cost and the license fee is ZERO, no server cost and no client cost. Buying a server Cd-release is a minor cost. Planning and installation time is the only actual and necessary cost
Yes, Most functions can be replaced by Open source software solutions with higher security and better control than a MS alternative. Planning and a spare Server or disk will help to minimize the interruption time.
The upgrade and the maintenance of the system takes time, but not more than any other upgrade. Each server can be installed in one or a couple of hours. Data should be transferred and users set up, this will take transfer time and up to 30 minutes per user, but not more. Installation and server configuration should be planned and scheduled, these times depends on size of the system.
It depends on a number of things, but it won't be slower!. Reports shows that Samba can handle maybe four times as many client systems as a Windows 2000 server before performance begins to drop off.
Savings are: The server software and license cost + Client licenses.
Total amounts depends on what software you use and how you buy it, but a minimum license cost of $100/year/user is not an unreasonable to expect.
A Linux distribution with no strings attached and unlimited usages cost between $50 and $150. Not including client software for office usage.
In addition to this you should add the maintenance and/or support fee.
You can buy support for Open source software if you do not want to handle that yourself.
In return for using Open Source software you should try to help the Open Source community.
This could be done in a number of ways, so you can give something back.
It could be problem reports, information about solved problems or writing some documentation or code.
You can get each software package separately from the Internet or you can download or buy a set of Cd's with a server system from a number of companies that packages the software together with a "simple to install program".
Companies like Red Hat, Mandrake and Suse is the most known. It does not matter much witch one you use, the server software is almost the same. But the installation and utilities may differ a little.
A general software install list is: Boot-loader, kernel, samba, backup-tools, printer server, webmin and drivers ( if any ) that are needed for your hardware.
If you install a system from one of the main distributions then that package contains all of this and more hardware support you probably need.
You get a system that can perform a wide range of server functions: File-server, Windows-master ? Domain-master, ... dhcp-server, ... Each part needs some configuration and this will take some initial time.
But there are nice configuration tools and help available.