Hello,
I'm an administrator of a small office.
We have about 20 users.
And have the following HW:

Dell PE2900(Domain Contoller,Exchange,SQL2000):
-Microsoft Small Business Server R2 2003 Std.
-1x Xeon Quad Core E5320 1,86Ghz
-4GB Memory
-8x 73GB SAS 15K rpm (Raid 5)
-Intel 10 Gigabit XF SR Server Adapter (Uplink to Switch)
-Quantum LTO2 Tape Drive 200/400gb

Custom Build(Terminal Server):
-Microsoft Windows Server R2 2003 Std.
-1x Intel Core2Duo 6400 2.13Ghz
-4GB Memory
-1x 250GB
-Intel Gigabit VT Quad Port Server Adapter

Switch: Dell PowerConnect 6248

We have 1 other old server wich wil eventually be removed.
And 2 (Pentium 2) workstations for the control of the airco and an RFID Door Access System.

The Terminal Server is basically a workstation with extra memory.
We have 2 types of users: Sales (all the sales employees have a laptop) and internal (own pc or thin-client)

15 Internal
5 Sales
-----+
Total of ±20 users

We want to get all internal users to the terminal server(s)
The sales users also occasionally log in the terminal server when they are working from home.

I think it best to have 2 terminal servers for fallback or for maintenance.

I would like to buy 1 new server and upgrade the PE2900 with more memory ±16gb
And use ESXi 3.5 on both servers to virtualise:
1x Small Business 2003 Std (exchange,domain controller)
2x Windows 2003/2008 Std (Terminal Servers)
2x Windows XP (Airco, Door Access)
1x Windows 2000 Server (Old Server app)
and maybe a Windows 2003/2008 Server with SQL 2005

What is the best way to store the Virtual machines?
Use the internal harddisks or a separate SAN,NAS or NFS server?

We don't have a big budget so i must be creative.

Thanks!!

Gr. Stephan